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zshcompsys (1)

名前

zshcompsys - zsh completion system

形式

Please see following description for synopsis

説明

ZSHCOMPSYS(1)               General Commands Manual              ZSHCOMPSYS(1)



NAME
       zshcompsys - zsh completion system

DESCRIPTION
       This describes the shell code for the `new' completion system, referred
       to as compsys.  It is written in shell functions based on the  features
       described in zshcompwid(1).

       The features are contextual, sensitive to the point at which completion
       is started.  Many completions are already provided.  For this reason, a
       user  can perform a great many tasks without knowing any details beyond
       how to initialize the system, which is described below  in  INITIALIZA-
       TION.

       The context that decides what completion is to be performed may be
       o      an  argument  or option position: these describe the position on
              the command line at which completion is requested.  For  example
              `first  argument  to  rmdir,  the  word  being completed names a
              directory';


       o      a special context, denoting an element in  the  shell's  syntax.
              For  example  `a  word  in  command  position' or `an array sub-
              script'.


       A full context specification  contains  other  elements,  as  we  shall
       describe.

       Besides  commands  names and contexts, the system employs two more con-
       cepts, styles and tags.  These provide ways for the user  to  configure
       the system's behaviour.

       Tags  play  a dual role.  They serve as a classification system for the
       matches, typically indicating a class of object that the user may  need
       to  distinguish.  For example, when completing arguments of the ls com-
       mand the user may prefer to try files before directories,  so  both  of
       these are tags.  They also appear as the rightmost element in a context
       specification.

       Styles modify various operations of the completion system, such as out-
       put formatting, but also what kinds of completers are used (and in what
       order), or which tags are examined.  Styles may  accept  arguments  and
       are  manipulated  using  the  zstyle  command  described in see zshmod-
       ules(1).

       In summary, tags describe what the completion objects  are,  and  style
       how they are to be completed.  At various points of execution, the com-
       pletion system checks what styles and/or tags are defined for the  cur-
       rent  context, and uses that to modify its behavior.  The full descrip-
       tion of context handling, which determines how tags and other  elements
       of the context influence the behaviour of styles, is described below in
       COMPLETION SYSTEM CONFIGURATION.

       When a completion is requested, a dispatcher function  is  called;  see
       the  description  of  _main_complete  in  the list of control functions
       below. This dispatcher decides which function should be called to  pro-
       duce the completions, and calls it. The result is passed to one or more
       completers, functions that implement individual completion  strategies:
       simple  completion, error correction, completion with error correction,
       menu selection, etc.

       More generally, the shell functions contained in the completion  system
       are of two types:
       o      those beginning `comp' are to be called directly; there are only
              a few of these;


       o      those beginning `_' are called  by  the  completion  code.   The
              shell  functions  of this set, which implement completion behav-
              iour and may be bound to keystrokes, are referred  to  as  `wid-
              gets'.  These proliferate as new completions are required.


INITIALIZATION
       If the system was installed completely, it should be enough to call the
       shell function compinit from your initialization  file;  see  the  next
       section.   However,  the  function  compinstall can be run by a user to
       configure various aspects of the completion system.

       Usually, compinstall will insert code into .zshrc, although if that  is
       not  writable  it will save it in another file and tell you that file's
       location.  Note that it is up to you to make sure that the lines  added
       to  .zshrc are actually run; you may, for example, need to move them to
       an earlier place in the file if .zshrc usually returns early.  So  long
       as you keep them all together (including the comment lines at the start
       and finish), you can rerun compinstall and it will correctly locate and
       modify  these lines.  Note, however, that any code you add to this sec-
       tion by hand is likely to be lost if you  rerun  compinstall,  although
       lines using the command `zstyle' should be gracefully handled.

       The  new  code  will  take effect next time you start the shell, or run
       .zshrc by hand; there is also an option to make them take effect  imme-
       diately.   However,  if  compinstall  has removed definitions, you will
       need to restart the shell to see the changes.

       To run compinstall you will need to make sure it is in a directory men-
       tioned in your fpath parameter, which should already be the case if zsh
       was properly configured as long as your startup files do not remove the
       appropriate  directories  from  fpath.   Then  it  must  be  autoloaded
       (`autoload -U compinstall' is recommended).  You can abort the  instal-
       lation any time you are being prompted for information, and your .zshrc
       will not be altered at all; changes only take place right at  the  end,
       where you are specifically asked for confirmation.

   Use of compinit
       This section describes the use of compinit to initialize completion for
       the current session when called directly; if you have  run  compinstall
       it will be called automatically from your .zshrc.

       To  initialize  the system, the function compinit should be in a direc-
       tory mentioned  in  the  fpath  parameter,  and  should  be  autoloaded
       (`autoload  -U  compinit'  is  recommended),  and  then  run  simply as
       `compinit'.  This will define a few utility functions, arrange for  all
       the necessary shell functions to be autoloaded, and will then re-define
       all widgets that do completion to use the new system.  If you  use  the
       menu-select  widget,  which  is  part  of  the zsh/complist module, you
       should make sure that that module is loaded before the call to compinit
       so  that  that  widget  is  also re-defined.  If completion styles (see
       below) are set up  to  perform  expansion  as  well  as  completion  by
       default,  and the TAB key is bound to expand-or-complete, compinit will
       rebind it to complete-word; this is necessary to use the  correct  form
       of expansion.

       Should  you need to use the original completion commands, you can still
       bind keys to the old widgets by putting a `.' in front  of  the  widget
       name, e.g. `.expand-or-complete'.

       To speed up the running of compinit, it can be made to produce a dumped
       configuration that will be read in on future invocations; this  is  the
       default,  but can be turned off by calling compinit with the option -D.
       The dumped file is .zcompdump in the  same  directory  as  the  startup
       files  (i.e.  $ZDOTDIR  or $HOME); alternatively, an explicit file name
       can be given  by  `compinit  -d  dumpfile'.   The  next  invocation  of
       compinit  will  read  the dumped file instead of performing a full ini-
       tialization.

       If the number of completion files changes, compinit will recognise this
       and produce a new dump file.  However, if the name of a function or the
       arguments in the first line of a #compdef function (as described below)
       change,  it is easiest to delete the dump file by hand so that compinit
       will re-create it the next time it is run.  The check performed to  see
       if  there are new functions can be omitted by giving the option -C.  In
       this case the dump file  will  only  be  created  if  there  isn't  one
       already.

       The  dumping  is  actually  done by another function, compdump, but you
       will only need to run this yourself if  you  change  the  configuration
       (e.g.  using  compdef)  and then want to dump the new one.  The name of
       the old dumped file will be remembered for this purpose.

       If the parameter _compdir is set, compinit uses it as a directory where
       completion  functions  can be found; this is only necessary if they are
       not already in the function search path.

       For security reasons compinit also  checks  if  the  completion  system
       would  use  files not owned by root or by the current user, or files in
       directories that are world- or group-writable or that are not owned  by
       root  or  by the current user.  If such files or directories are found,
       compinit will ask if the completion system should really be  used.   To
       avoid  these tests and make all files found be used without asking, use
       the option -u, and to make compinit silently ignore all insecure  files
       and  directories  use  the  option  -i.  This security check is skipped
       entirely when the -C option is given.

       The security check can be retried at any time by running  the  function
       compaudit.   This  is  the  same check used by compinit, but when it is
       executed directly any changes to fpath are made local to  the  function
       so they do not persist.  The directories to be checked may be passed as
       arguments; if none are given, compaudit uses fpath and _compdir to find
       completion  system  directories, adding missing ones to fpath as neces-
       sary.  To force a check of exactly the directories currently  named  in
       fpath,  set  _compdir  to  an  empty string before calling compaudit or
       compinit.

       The function bashcompinit provides compatibility with  bash's  program-
       mable  completion system.  When run it will define the functions, comp-
       gen and complete which correspond to the bash builtins  with  the  same
       names.   It  will then be possible to use completion specifications and
       functions written for bash.

   Autoloaded files
       The convention for autoloaded functions used in completion is that they
       start with an underscore; as already mentioned, the fpath/FPATH parame-
       ter must contain the directory in which they are stored.   If  zsh  was
       properly  installed on your system, then fpath/FPATH automatically con-
       tains the required directories for the standard functions.

       For incomplete installations, if compinit does not  find  enough  files
       beginning with an underscore (fewer than twenty) in the search path, it
       will try to find more by adding the directory _compdir  to  the  search
       path.  If that directory has a subdirectory named Base, all subdirecto-
       ries will be added to the path.  Furthermore, if the subdirectory  Base
       has  a subdirectory named Core, compinit will add all subdirectories of
       the subdirectories to the path: this allows the functions to be in  the
       same format as in the zsh source distribution.

       When  compinit  is  run,  it  searches  all  such  files accessible via
       fpath/FPATH and reads the first line of each of them.  This line should
       contain  one  of the tags described below.  Files whose first line does
       not start with one of these tags are not considered to be part  of  the
       completion system and will not be treated specially.

       The tags are:

       #compdef name ... [ -{p|P} pattern ... [ -N name ... ] ]
              The  file  will be made autoloadable and the function defined in
              it will be called when completing names, each of which is either
              the name of a command whose arguments are to be completed or one
              of a number of special contexts in the form -context-  described
              below.

              Each  name may also be of the form `cmd=service'.  When complet-
              ing the command cmd, the function typically behaves  as  if  the
              command   (or  special  context)  service  was  being  completed
              instead.  This provides a way of altering the behaviour of func-
              tions that can perform many different completions.  It is imple-
              mented by setting the parameter $service when calling the  func-
              tion;  the  function may choose to interpret this how it wishes,
              and simpler functions will probably ignore it.

              If the #compdef line contains one of the options -p or  -P,  the
              words  following are taken to be patterns.  The function will be
              called when completion is attempted for  a  command  or  context
              that  matches  one  of  the patterns.  The options -p and -P are
              used to specify patterns to be tried before or after other  com-
              pletions  respectively.  Hence -P may be used to specify default
              actions.

              The option -N is used after a list following -p or -P; it speci-
              fies that remaining words no longer define patterns.  It is pos-
              sible to toggle between the three options as many times as  nec-
              essary.

       #compdef -k style key-sequence ...
              This  option  creates  a widget behaving like the builtin widget
              style and binds it to the  given  key-sequences,  if  any.   The
              style  must  be  one of the builtin widgets that perform comple-
              tion, namely complete-word, delete-char-or-list,  expand-or-com-
              plete,  expand-or-complete-prefix,  list-choices, menu-complete,
              menu-expand-or-complete,  or  reverse-menu-complete.    If   the
              zsh/complist  module  is  loaded  (see zshmodules(1)) the widget
              menu-select is also available.

              When one of the key-sequences is typed, the function in the file
              will  be  invoked to generate the matches.  Note that a key will
              not be re-bound if it already was (that is, was bound  to  some-
              thing  other  than  undefined-key).   The widget created has the
              same name as the file and can be bound to any other  keys  using
              bindkey as usual.

       #compdef -K widget-name style key-sequence [ name style seq ... ]
              This is similar to -k except that only one key-sequence argument
              may be given for each  widget-name  style  pair.   However,  the
              entire  set  of three arguments may be repeated with a different
              set of arguments.  Note in particular that the widget-name  must
              be  distinct  in  each  set.  If it does not begin with `_' this
              will be added.  The widget-name should not clash with  the  name
              of  any existing widget: names based on the name of the function
              are most useful.  For example,

                     #compdef -K _foo_complete complete-word "^X^C" \
                       _foo_list list-choices "^X^D"

              (all on one line) defines a widget _foo_complete for completion,
              bound  to  `^X^C',  and a widget _foo_list for listing, bound to
              `^X^D'.

       #autoload [ options ]
              Functions with the #autoload tag are marked for autoloading  but
              are  not  otherwise treated specially.  Typically they are to be
              called from within one of the completion functions.  Any options
              supplied  will  be passed to the autoload builtin; a typical use
              is +X to force the function to be loaded immediately.  Note that
              the -U and -z flags are always added implicitly.

       The  #  is part of the tag name and no white space is allowed after it.
       The #compdef tags use the compdef function described  below;  the  main
       difference is that the name of the function is supplied implicitly.

       The special contexts for which completion functions can be defined are:

       -array-value-
              The right hand side of an array-assignment (`name=(...)')

       -brace-parameter-
              The name of a parameter expansion within braces (`${...}')

       -assign-parameter-
              The  name of a parameter in an assignment, i.e. on the left hand
              side of an `='

       -command-
              A word in command position

       -condition-
              A word inside a condition (`[[...]]')

       -default-
              Any word for which no other completion is defined

       -equal-
              A word beginning with an equals sign

       -first-
              This is tried before any other completion function.   The  func-
              tion  called  may  set the _compskip parameter to one of various
              values: all: no further completion is attempted; a  string  con-
              taining  the substring patterns: no pattern completion functions
              will be called; a string containing default:  the  function  for
              the  `-default-'  context  will  not  be  called,  but functions
              defined for commands will be.

       -math- Inside mathematical contexts, such as `((...))'

       -parameter-
              The name of a parameter expansion (`$...')

       -redirect-
              The word after a redirection operator.

       -subscript-
              The contents of a parameter subscript.

       -tilde-
              After an initial tilde (`~'), but before the first slash in  the
              word.

       -value-
              On the right hand side of an assignment.

       Default  implementations  are  supplied for each of these contexts.  In
       most cases the context -context-  is  implemented  by  a  corresponding
       function  _context,  for example the context `-tilde-' and the function
       `_tilde').

       The contexts -redirect- and -value- allow extra context-specific infor-
       mation.  (Internally, this is handled by the functions for each context
       calling the function _dispatch.)  The extra information is added  sepa-
       rated by commas.

       For  the -redirect- context, the extra information is in the form `-re-
       direct-,op,command', where op is the redirection operator  and  command
       is  the name of the command on the line.  If there is no command on the
       line yet, the command field will be empty.

       For the -value- context, the form is `-value-,name,command', where name
       is  the  name of the parameter on the left hand side of the assignment.
       In  the  case  of  elements  of  an  associative  array,  for   example
       `assoc=(key <TAB>', name is expanded to `name-key'.  In certain special
       contexts, such as completing after `make  CFLAGS=',  the  command  part
       gives the name of the command, here make; otherwise it is empty.

       It  is  not necessary to define fully specific completions as the func-
       tions provided  will  try  to  generate  completions  by  progressively
       replacing  the elements with `-default-'.  For example, when completing
       after `foo=<TAB>', _value will try the names `-value-,foo,'  (note  the
       empty          command          part),          `-value-,foo,-default-'
       and`-value-,-default-,-default-', in that order, until it finds a func-
       tion to handle the context.

       As an example:

              compdef '_files -g "*.log"' '-redirect-,2>,-default-'

       completes  files matching `*.log' after `2> <TAB>' for any command with
       no more specific handler defined.

       Also:

              compdef _foo -value-,-default-,-default-

       specifies that _foo provides completions for the values  of  parameters
       for  which  no special function has been defined.  This is usually han-
       dled by the function _value itself.

       The same lookup rules are used when looking  up  styles  (as  described
       below); for example

              zstyle ':completion:*:*:-redirect-,2>,*:*' file-patterns '*.log'

       is  another  way  to  make  completion  after `2> <TAB>' complete files
       matching `*.log'.

   Functions
       The following function  is  defined  by  compinit  and  may  be  called
       directly.

       compdef [ -ane ] function name ... [ -{p|P} pattern ... [ -N name ...]]
       compdef -d name ...
       compdef -k [ -an ] function style key-sequence [ key-sequence ... ]
       compdef -K [ -an ] function name style key-seq [ name style seq ... ]
              The  first  form  defines the function to call for completion in
              the given contexts as described for the #compdef tag above.

              Alternatively, all the arguments may  have  the  form  `cmd=ser-
              vice'.   Here  service  should  already  have  been  defined  by
              `cmd1=service' lines in #compdef files, as described above.  The
              argument for cmd will be completed in the same way as service.

              The  function  argument may alternatively be a string containing
              almost any shell code.  If the string contains  an  equal  sign,
              the  above  will  take precedence.  The option -e may be used to
              specify the first argument is to be evaluated as shell code even
              if it contains an equal sign.  The string will be executed using
              the eval builtin command to generate completions.  This provides
              a  way  of  avoiding having to define a new completion function.
              For example, to complete files ending in `.h'  as  arguments  to
              the command foo:

                     compdef '_files -g "*.h"' foo

              The  option  -n prevents any completions already defined for the
              command or context from being overwritten.

              The option -d deletes any completion defined for the command  or
              contexts listed.

              The  names  may  also contain -p, -P and -N options as described
              for the #compdef tag.  The effect on the argument list is  iden-
              tical,  switching  between  definitions  of  patterns tried ini-
              tially, patterns tried finally, and  normal  commands  and  con-
              texts.

              The  parameter $_compskip may be set by any function defined for
              a pattern context.  If it is set to a value containing the  sub-
              string  `patterns' none of the pattern-functions will be called;
              if it is set to a value containing the substring `all', no other
              function will be called.

              The  form  with  -k  defines  a widget with the same name as the
              function that will be called for each of the key-sequences; this
              is  like  the #compdef -k tag.  The function should generate the
              completions needed and will otherwise behave  like  the  builtin
              widget  whose  name is given as the style argument.  The widgets
              usable  for  this   are:   complete-word,   delete-char-or-list,
              expand-or-complete,   expand-or-complete-prefix,   list-choices,
              menu-complete,  menu-expand-or-complete,  and  reverse-menu-com-
              plete,  as  well  as  menu-select  if the zsh/complist module is
              loaded.  The option -n prevents the key being  bound  if  it  is
              already to bound to something other than undefined-key.

              The  form  with -K is similar and defines multiple widgets based
              on the same function, each of which requires the  set  of  three
              arguments name, style and key-sequence, where the latter two are
              as for -k and the first must be a unique widget  name  beginning
              with an underscore.

              Wherever  applicable, the -a option makes the function autoload-
              able, equivalent to autoload -U function.

       The function compdef can be used to associate existing completion func-
       tions with new commands.  For example,

              compdef _pids foo

       uses the function _pids to complete process IDs for the command foo.

       Note  also the _gnu_generic function described below, which can be used
       to complete options for commands that understand the `--help' option.

COMPLETION SYSTEM CONFIGURATION
       This section gives a short overview of how the completion system works,
       and  then  more  detail on how users can configure how and when matches
       are generated.

   Overview
       When completion is attempted somewhere on the command line the  comple-
       tion system begins building the context.  The context represents every-
       thing that the shell knows about the meaning of the  command  line  and
       the  significance of the cursor position.  This takes account of a num-
       ber of things including the command word (such as `grep' or `zsh')  and
       options  to which the current word may be an argument (such as the `-o'
       option to zsh which takes a shell option as an argument).

       The context starts out very generic ("we are beginning  a  completion")
       and becomes more specific as more is learned ("the current word is in a
       position that is usually a command name" or "the current word might  be
       a  variable  name"  and so on).  Therefore the context will vary during
       the same call to the completion system.

       This context information is condensed into a string consisting of  mul-
       tiple  fields  separated by colons, referred to simply as `the context'
       in the remainder of the documentation.  Note that a user of the comple-
       tion  system rarely needs to compose a context string, unless for exam-
       ple a new function is being written to perform  completion  for  a  new
       command.   What a user may need to do is compose a style pattern, which
       is matched against a context when needed to look  up  context-sensitive
       options that configure the completion system.

       The  next  few  paragraphs explain how a context is composed within the
       completion function suite.  Following that is discussion of how  styles
       are  defined.  Styles determine such things as how the matches are gen-
       erated, similarly to shell options but with much  more  control.   They
       are defined with the zstyle builtin command (see zshmodules(1)).

       The  context string always consists of a fixed set of fields, separated
       by colons and with a leading colon before the first.  Fields which  are
       not yet known are left empty, but the surrounding colons appear anyway.
       The fields are always in the order  :completion:function:completer:com-
       mand:argument:tag.  These have the following meaning:

       o      The literal string completion, saying that this style is used by
              the completion system.   This  distinguishes  the  context  from
              those used by, for example, zle widgets and ZFTP functions.


       o      The function, if completion is called from a named widget rather
              than through the normal completion system.   Typically  this  is
              blank,  but  it is set by special widgets such as predict-on and
              the various functions in the Widget directory of  the  distribu-
              tion to the name of that function, often in an abbreviated form.


       o      The completer currently active, the name of the function without
              the leading underscore and with other underscores  converted  to
              hyphens.   A `completer' is in overall control of how completion
              is to be performed; `complete' is the simplest, but  other  com-
              pleters exist to perform related tasks such as correction, or to
              modify the behaviour of a  later  completer.   See  the  section
              `Control Functions' below for more information.


       o      The command or a special -context-, just at it appears following
              the #compdef tag or the compdef function.  Completion  functions
              for commands that have sub-commands usually modify this field to
              contain the name of the command followed by a minus sign and the
              sub-command.   For  example, the completion function for the cvs
              command sets this field to cvs-add when completing arguments  to
              the add subcommand.


       o      The  argument; this indicates which command line or option argu-
              ment we are completing.  For command  arguments  this  generally
              takes  the  form  argument-n, where n is the number of the argu-
              ment, and for arguments to options the form option-opt-n where n
              is  the  number of the argument to option opt.  However, this is
              only the case if  the  command  line  is  parsed  with  standard
              UNIX-style options and arguments, so many completions do not set
              this.


       o      The tag.  As described previously, tags are used to discriminate
              between  the types of matches a completion function can generate
              in a certain context.  Any completion function may use  any  tag
              name  it  likes,  but  a  list  of the more common ones is given
              below.


       The context is gradually put together as the  functions  are  executed,
       starting  with  the  main  entry point, which adds :completion: and the
       function element if necessary.  The completer then adds  the  completer
       element.   The  contextual  completion  adds  the  command and argument
       options.  Finally, the tag is added when the types  of  completion  are
       known.  For example, the context name

              :completion::complete:dvips:option-o-1:files

       says  that normal completion was attempted as the first argument to the
       option -o of the command dvips:

              dvips -o ...

       and the completion function will generate filenames.

       Usually completion will be tried for all  possible  tags  in  an  order
       given  by  the  completion  function.   However, this can be altered by
       using the tag-order style.  Completion is then restricted to  the  list
       of given tags in the given order.

       The  _complete_help  bindable  command  shows all the contexts and tags
       available for completion at a particular point.  This provides an  easy
       way  of  finding  information  for  tag-order  and other styles.  It is
       described in the section `Bindable Commands' below.

       When looking up styles the completion system uses full  context  names,
       including  the tag.  Looking up the value of a style therefore consists
       of two things: the context, which is matched to the most specific (best
       fitting) style pattern, and the name of the style itself, which must be
       matched exactly.  The following examples demonstrate  that  style  pat-
       terns  may  be  loosely  defined  for  styles that apply broadly, or as
       tightly defined as desired for styles that apply  in  narrower  circum-
       stances.

       For example, many completion functions can generate matches in a simple
       and a verbose form and use the  verbose  style  to  decide  which  form
       should be used.  To make all such functions use the verbose form, put

              zstyle ':completion:*' verbose yes

       in  a startup file (probably .zshrc).  This gives the verbose style the
       value yes in every context inside the completion  system,  unless  that
       context has a more specific definition.  It is best to avoid giving the
       context as `*' in case the style has some meaning outside  the  comple-
       tion system.

       Many  such general purpose styles can be configured simply by using the
       compinstall function.

       A more specific example of the use of the verbose style is by the  com-
       pletion  for  the kill builtin.  If the style is set, the builtin lists
       full job texts and process command lines; otherwise it shows  the  bare
       job numbers and PIDs.  To turn the style off for this use only:

              zstyle ':completion:*:*:kill:*:*' verbose no

       For  even  more  control,  the  style can use one of the tags `jobs' or
       `processes'.  To turn off verbose display only for jobs:

              zstyle ':completion:*:*:kill:*:jobs' verbose no

       The -e option to zstyle even allows completion function code to  appear
       as  the  argument  to  a style; this requires some understanding of the
       internals of completion functions (see see zshcompwid(1))).  For  exam-
       ple,

              zstyle -e ':completion:*' hosts 'reply=($myhosts)'

       This  forces  the value of the hosts style to be read from the variable
       myhosts each time a host name is needed; this is useful if the value of
       myhosts  can  change  dynamically.  For another useful example, see the
       example in the description of the file-list style below.  This form can
       be slow and should be avoided for commonly examined styles such as menu
       and list-rows-first.

       Note that the order in which styles are defined does  not  matter;  the
       style  mechanism uses the most specific possible match for a particular
       style to determine the set of values.  More precisely, strings are pre-
       ferred  over  patterns  (for  example, `:completion::complete:::foo' is
       more specific than `:completion::complete:::*'),  and  longer  patterns
       are preferred over shorter patterns.

       A good rule of thumb is that any completion style pattern that needs to
       include more than one wildcard (*) and that does not end in a tag name,
       should  include  all  six  colons  (:), possibly surrounding additional
       wildcards.

       Style names like those of tags are arbitrary and depend on the  comple-
       tion  function.   However,  the following two sections list some of the
       most common tags and styles.

   Standard Tags
       Some of the following are only used when looking up  particular  styles
       and do not refer to a type of match.

       accounts
              used to look up the users-hosts style

       all-expansions
              used by the _expand completer when adding the single string con-
              taining all possible expansions

       all-files
              for the names of all files (as distinct from a  particular  sub-
              set, see the globbed-files tag).

       arguments
              for arguments to a command

       arrays for names of array parameters

       association-keys
              for  keys  of  associative arrays; used when completing inside a
              subscript to a parameter of this type

       bookmarks
              when completing bookmarks (e.g. for URLs and the  zftp  function
              suite)

       builtins
              for names of builtin commands

       characters
              for  single  characters  in  arguments of commands such as stty.
              Also used when completing character  classes  after  an  opening
              bracket

       colormapids
              for X colormap ids

       colors for color names

       commands
              for  names  of external commands.  Also used by complex commands
              such as cvs when completing names subcommands.

       contexts
              for contexts in arguments to the zstyle builtin command

       corrections
              used by the _approximate and _correct  completers  for  possible
              corrections

       cursors
              for cursor names used by X programs

       default
              used  in  some  contexts to provide a way of supplying a default
              when more specific tags are also valid.  Note that this  tag  is
              used when only the function field of the context name is set

       descriptions
              used  when  looking up the value of the format style to generate
              descriptions for types of matches

       devices
              for names of device special files

       directories
              for names of directories -- local-directories  is  used  instead
              when  completing  arguments  of  cd and related builtin commands
              when the cdpath array is set

       directory-stack
              for entries in the directory stack

       displays
              for X display names

       domains
              for network domains

       email-plugin
              for  email  addresses  from  the  `_email-plugin'   backend   of
              _email_addresses

       expansions
              used  by  the _expand completer for individual words (as opposed
              to the complete set of expansions) resulting from the  expansion
              of a word on the command line

       extensions
              for X server extensions

       file-descriptors
              for numbers of open file descriptors

       files  the generic file-matching tag used by functions completing file-
              names

       fonts  for X font names

       fstypes
              for file system types (e.g. for the mount command)

       functions
              names of functions -- normally shell functions, although certain
              commands may understand other kinds of function

       globbed-files
              for filenames when the name has been generated by pattern match-
              ing

       groups for names of user groups

       history-words
              for words from the history

       hosts  for hostnames

       indexes
              for array indexes

       jobs   for jobs (as listed by the `jobs' builtin)

       interfaces
              for network interfaces

       keymaps
              for names of zsh keymaps

       keysyms
              for names of X keysyms

       libraries
              for names of system libraries

       limits for system limits

       local-directories
              for names of directories that are subdirectories of the  current
              working  directory  when  completing arguments of cd and related
              builtin commands (compare path-directories) -- when  the  cdpath
              array is unset, directories is used instead

       manuals
              for names of manual pages

       mailboxes
              for e-mail folders

       maps   for map names (e.g. NIS maps)

       messages
              used to look up the format style for messages

       modifiers
              for names of X modifiers

       modules
              for modules (e.g. zsh modules)

       my-accounts
              used to look up the users-hosts style

       named-directories
              for  named  directories  (you  wouldn't have guessed that, would
              you?)

       names  for all kinds of names

       newsgroups
              for USENET groups

       nicknames
              for nicknames of NIS maps

       options
              for command options

       original
              used by the _approximate, _correct and _expand  completers  when
              offering the original string as a match

       other-accounts
              used to look up the users-hosts style

       other-files
              for  the names of any non-directory files.  This is used instead
              of all-files when the list-dirs-first style is in effect.

       packages
              for packages (e.g. rpm or installed Debian packages)

       parameters
              for names of parameters

       path-directories
              for names of directories found by  searching  the  cdpath  array
              when  completing  arguments  of  cd and related builtin commands
              (compare local-directories)

       paths  used to look up the values of the  expand,  ambiguous  and  spe-
              cial-dirs styles

       pods   for perl pods (documentation files)

       ports  for communication ports

       prefixes
              for prefixes (like those of a URL)

       printers
              for print queue names

       processes
              for process identifiers

       processes-names
              used  to  look up the command style when generating the names of
              processes for killall

       sequences
              for sequences (e.g. mh sequences)

       sessions
              for sessions in the zftp function suite

       signals
              for signal names

       strings
              for strings (e.g. the replacement strings  for  the  cd  builtin
              command)

       styles for styles used by the zstyle builtin command

       suffixes
              for filename extensions

       tags   for tags (e.g. rpm tags)

       targets
              for makefile targets

       time-zones
              for time zones (e.g. when setting the TZ parameter)

       types  for types of whatever (e.g. address types for the xhost command)

       urls   used to look up the urls and local styles when completing URLs

       users  for usernames

       values for one of a set of values in certain lists

       variant
              used  by _pick_variant to look up the command to run when deter-
              mining what program is installed for a particular command name.

       visuals
              for X visuals

       warnings
              used to look up the format style for warnings

       widgets
              for zsh widget names

       windows
              for IDs of X windows

       zsh-options
              for shell options

   Standard Styles
       Note that the values of several of these styles represent boolean  val-
       ues.   Any  of the strings `true', `on', `yes', and `1' can be used for
       the value `true' and any of the strings `false', `off', `no',  and  `0'
       for  the  value `false'.  The behavior for any other value is undefined
       except where explicitly mentioned.  The default  value  may  be  either
       `true' or `false' if the style is not set.

       Some  of  these  styles  are tested first for every possible tag corre-
       sponding to a type of match, and if no style was found, for the default
       tag.   The  most  notable styles of this type are menu, list-colors and
       styles  controlling  completion  listing  such   as   list-packed   and
       last-prompt.   When tested for the default tag, only the function field
       of the context will be set so that a style using the default  tag  will
       normally be defined along the lines of:

              zstyle ':completion:*:default' menu ...

       accept-exact
              This is tested for the default tag in addition to the tags valid
              for the current context.  If it is set to `true' and any of  the
              trial  matches  is  the  same as the string on the command line,
              this match will immediately be accepted (even if it would other-
              wise be considered ambiguous).

              When  completing  pathnames (where the tag used is `paths') this
              style accepts any number of patterns as the value in addition to
              the  boolean  values.   Pathnames matching one of these patterns
              will be accepted immediately even if the command  line  contains
              some more partially typed pathname components and these match no
              file under the directory accepted.

              This style is also used by the _expand completer  to  decide  if
              words  beginning  with  a tilde or parameter expansion should be
              expanded.  For example, if there are parameters foo and  foobar,
              the  string  `$foo' will only be expanded if accept-exact is set
              to `true'; otherwise the completion system will  be  allowed  to
              complete  $foo  to  $foobar.  If the style is set to `continue',
              _expand will add the expansion as a  match  and  the  completion
              system will also be allowed to continue.

       accept-exact-dirs
              This  is used by filename completion.  Unlike accept-exact it is
              a boolean.  By default, filename completion examines all  compo-
              nents  of  a path to see if there are completions of that compo-
              nent, even if the component matches an existing directory.   For
              example,  when completion after /usr/bin/, the function examines
              possible completions to /usr.

              When this style is `true', any prefix of a path that matches  an
              existing  directory  is accepted without any attempt to complete
              it further.  Hence, in the given example, the path /usr/bin/  is
              accepted immediately and completion tried in that directory.

              If  you  wish  to  inhibit  this  behaviour  entirely,  set  the
              path-completion style (see below) to `false'.

       add-space
              This style is used by the _expand completer.  If  it  is  `true'
              (the  default), a space will be inserted after all words result-
              ing from the expansion, or a slash  in  the  case  of  directory
              names.   If  the  value is `file', the completer will only add a
              space to names of existing files.  Either a  boolean  `true'  or
              the value `file' may be combined with `subst', in which case the
              completer will not add a  space  to  words  generated  from  the
              expansion of a substitution of the form `$(...)' or `${...}'.

              The  _prefix completer uses this style as a simple boolean value
              to decide if a space should be inserted before the suffix.

       ambiguous
              This applies when completing non-final  components  of  filename
              paths,  in  other  words  those with a trailing slash.  If it is
              set, the cursor is left after  the  first  ambiguous  component,
              even  if  menu completion is in use.  The style is always tested
              with the paths tag.

       assign-list
              When completing after an equals sign that is being treated as an
              assignment,  the  completion  system normally completes only one
              filename.  In some cases the value  may be a list  of  filenames
              separated  by colons, as with PATH and similar parameters.  This
              style can be set to a list of patterns  matching  the  names  of
              such parameters.

              The  default  is  to  complete  lists  when the word on the line
              already contains a colon.

       auto-description
              If set, this style's value will be used as the  description  for
              options  that are not described by the completion functions, but
              that have exactly one argument.  The sequence `%d' in the  value
              will  be replaced by the description for this argument.  Depend-
              ing on personal preferences, it may be useful to set this  style
              to  something  like  `specify: %d'.  Note that this may not work
              for some commands.

       avoid-completer
              This is used by the _all_matches  completer  to  decide  if  the
              string  consisting  of  all  matches should be added to the list
              currently being generated.  Its value is a list of names of com-
              pleters.  If any of these is the name of the completer that gen-
              erated the matches in this completion, the string  will  not  be
              added.

              The  default value for this style is `_expand _old_list _correct
              _approximate', i.e. it  contains  the  completers  for  which  a
              string with all matches will almost never be wanted.

       cache-path
              This  style  defines  the  path where any cache files containing
              dumped completion data  are  stored.   It  defaults  to  `$ZDOT-
              DIR/.zcompcache',  or  `$HOME/.zcompcache'  if  $ZDOTDIR  is not
              defined.  The completion cache  will  not  be  used  unless  the
              use-cache style is set.

       cache-policy
              This  style  defines the function that will be used to determine
              whether a cache  needs  rebuilding.   See  the  section  on  the
              _cache_invalid function below.

       call-command
              This style is used in the function for commands such as make and
              ant where calling the command directly to generate matches  suf-
              fers  problems such as being slow or, as in the case of make can
              potentially cause actions in the makefile to be executed. If  it
              is  set to `true' the command is called to generate matches. The
              default value of this style is `false'.

       command
              In many places, completion functions need to call external  com-
              mands  to  generate  the list of completions.  This style can be
              used to override the command that is called in some such  cases.
              The  elements of the value are joined with spaces to form a com-
              mand line to execute.  The value can also start with  a  hyphen,
              in  which  case the usual command will be added to the end; this
              is most useful for putting `builtin' or `command'  in  front  to
              make  sure  the  appropriate version of a command is called, for
              example to avoid calling a shell function with the same name  as
              an external command.

              As an example, the completion function for process IDs uses this
              style with the processes tag to generate the IDs to complete and
              the  list  of  processes  to  display  (if  the verbose style is
              `true').  The list produced by the command should look like  the
              output  of the ps command.  The first line is not displayed, but
              is searched for the string `PID' (or `pid') to find the position
              of the process IDs in the following lines.  If the line does not
              contain `PID', the first numbers in each of the other lines  are
              taken as the process IDs to complete.

              Note  that  the  completion  function  generally has to call the
              specified command for each attempt to  generate  the  completion
              list.   Hence care should be taken to specify only commands that
              take a short time to run, and in particular to  avoid  any  that
              may never terminate.

       command-path
              This  is  a  list  of directories to search for commands to com-
              plete.  The default for this style is the value of  the  special
              parameter path.

       commands
              This  is  used  by  the function completing sub-commands for the
              system initialisation scripts (residing in /etc/init.d or  some-
              where  not too far away from that).  Its values give the default
              commands to complete for those commands for which the completion
              function isn't able to find them out automatically.  The default
              for this style are the two strings `start' and `stop'.

       complete
              This is used by the _expand_alias function  when  invoked  as  a
              bindable  command.  If set to `true' and the word on the command
              line is not the name of an alias, matching alias names  will  be
              completed.

       complete-options
              This  is  used  by  the  completer for cd, chdir and pushd.  For
              these commands a - is used to introduce a directory stack  entry
              and  completion  of  these  is  far  more common than completing
              options.  Hence unless the value of this style is `true' options
              will  not  be  completed,  even  after  an  initial -.  If it is
              `true', options will be completed  after  an  initial  -  unless
              there is a preceding -- on the command line.

       completer
              The  strings  given as the value of this style provide the names
              of the completer functions to use. The available completer func-
              tions are described in the section `Control Functions' below.

              Each  string may be either the name of a completer function or a
              string of the form `function:name'.  In the first case the  com-
              pleter  field  of  the context will contain the name of the com-
              pleter without the leading underscore and with all other  under-
              scores  replaced by hyphens.  In the second case the function is
              the name of the completer to call, but the context will  contain
              the user-defined name in the completer field of the context.  If
              the name starts with a hyphen, the string for the  context  will
              be build from the name of the completer function as in the first
              case with the name appended to it.  For example:

                     zstyle ':completion:*' completer _complete _complete:-foo

              Here, completion will call the _complete completer  twice,  once
              using  `complete' and once using `complete-foo' in the completer
              field of the context.  Normally, using the same  completer  more
              than  once  only makes sense when used with the `functions:name'
              form, because otherwise the context name will be the same in all
              calls to the completer; possible exceptions to this rule are the
              _ignored and _prefix completers.

              The default value for this style is `_complete  _ignored':  only
              completion  will be done, first using the ignored-patterns style
              and the $fignore array and then without ignoring matches.

       condition
              This style is used by the _list completer function to decide  if
              insertion  of  matches  should  be  delayed unconditionally. The
              default is `true'.

       delimiters
              This style is used when adding a delimiter for use with  history
              modifiers  or glob qualifiers that have delimited arguments.  It
              is an array of preferred delimiters to add.  Non-special charac-
              ters are preferred as the completion system may otherwise become
              confused.  The default list is :, +, /, -, %.  The list  may  be
              empty to force a delimiter to be typed.

       disabled
              If  this is set to `true', the _expand_alias completer and bind-
              able command will try to  expand  disabled  aliases,  too.   The
              default is `false'.

       domains
              A  list  of names of network domains for completion.  If this is
              not  set,  domain  names   will   be   taken   from   the   file
              /etc/resolv.conf.

       environ
              The environ style is used when completing for `sudo'.  It is set
              to an array of `VAR=value' assignments to be exported  into  the
              local  environment  before the completion for the target command
              is invoked.
              zstyle ':completion:*:sudo::' environ \
                PATH="/sbin:/usr/sbin:$PATH" HOME="/root"

       expand This style is used when completing strings consisting of  multi-
              ple parts, such as path names.

              If one of its values is the string `prefix', the partially typed
              word from the line will be expanded as far as possible  even  if
              trailing parts cannot be completed.

              If  one of its values is the string `suffix', matching names for
              components after the first ambiguous one  will  also  be  added.
              This  means that the resulting string is the longest unambiguous
              string possible.  However, menu completion can be used to  cycle
              through all matches.

       fake   This  style may be set for any completion context.  It specifies
              additional strings that will always be completed  in  that  con-
              text.  The form of each string is `value:description'; the colon
              and description may be omitted, but any literal colons in  value
              must  be  quoted  with a backslash.  Any description provided is
              shown alongside the value in completion listings.

              It is important to use a sufficiently restrictive  context  when
              specifying  fake  strings.   Note that the styles fake-files and
              fake-parameters  provide  additional  features  when  completing
              files or parameters.

       fake-always
              This  works  identically  to  the  fake  style  except  that the
              ignored-patterns style is not applied to it.  This makes it pos-
              sible  to  override  a  set of matches completely by setting the
              ignored patterns to `*'.

              The following shows a way of supplementing any  tag  with  arbi-
              trary  data,  but  having  it behave for display purposes like a
              separate tag.  In this  example  we  use  the  features  of  the
              tag-order  style  to  divide  the named-directories tag into two
              when performing completion with the standard completer  complete
              for  arguments  of cd.  The tag named-directories-normal behaves
              as normal, but the tag named-directories-mine contains  a  fixed
              set  of  directories.   This  has the effect of adding the match
              group `extra directories' with the given completions.

                     zstyle ':completion::complete:cd:*' tag-order \
                       'named-directories:-mine:extra\ directories
                       named-directories:-normal:named\ directories *'
                     zstyle ':completion::complete:cd:*:named-directories-mine' \
                       fake-always mydir1 mydir2
                     zstyle ':completion::complete:cd:*:named-directories-mine' \
                       ignored-patterns '*'

       fake-files
              This style is used when completing files and looked up without a
              tag.   Its values are of the form `dir:names...'.  This will add
              the names (strings separated by spaces) as possible matches when
              completing  in  the  directory dir, even if no such files really
              exist.  The dir may be a pattern; pattern characters  or  colons
              in  dir  should  be quoted with a backslash to be treated liter-
              ally.

              This can be useful on systems that support special file  systems
              whose  top-level  pathnames  can not be listed or generated with
              glob patterns.  It can also be used for  directories  for  which
              one does not have read permission.

              The  pattern  form can be used to add a certain `magic' entry to
              all directories on a particular file system.

       fake-parameters
              This is used by the completion  function  for  parameter  names.
              Its values are names of parameters that might not yet be set but
              should be completed nonetheless.  Each name may also be followed
              by  a  colon  and  a string specifying the type of the parameter
              (like `scalar', `array' or `integer').  If the  type  is  given,
              the  name  will only be completed if parameters of that type are
              required in the particular context.  Names for which no type  is
              specified will always be completed.

       file-list
              This  style  controls whether files completed using the standard
              builtin mechanism are to be listed with a long list  similar  to
              ls  -l.   Note  that this feature uses the shell module zsh/stat
              for file information; this loads the  builtin  stat  which  will
              replace any external stat executable.  To avoid this the follow-
              ing code can be included in an initialization file:

                     zmodload -i zsh/stat
                     disable stat

              The style may either be set to a `true' value (or `all'), or one
              of  the  values `insert' or `list', indicating that files are to
              be listed in long format in all circumstances, or when  attempt-
              ing  to  insert  a file name, or when listing file names without
              attempting to insert one.

              More generally, the value may be an array of any  of  the  above
              values, optionally followed by =num.  If num is present it gives
              the maximum number of matches for which long listing style  will
              be used.  For example,

                     zstyle ':completion:*' file-list list=20 insert=10

              specifies  that  long  format will be used when listing up to 20
              files or inserting a file with up  to  10  matches  (assuming  a
              listing  is to be shown at all, for example on an ambiguous com-
              pletion), else short format will be used.

                     zstyle -e ':completion:*' file-list \
                            '(( ${+NUMERIC} )) && reply=(true)'

              specifies that long format will be used any time a numeric argu-
              ment is supplied, else short format.

       file-patterns
              This  is used by the standard function for completing filenames,
              _files.  If the style is unset up to  three  tags  are  offered,
              `globbed-files',`directories'  and `all-files', depending on the
              types of files  expected by the caller of _files.  The first two
              (`globbed-files'   and   `directories')   are  normally  offered
              together to make it easier to complete files in sub-directories.

              The file-patterns style provides  alternatives  to  the  default
              tags, which are not used.  Its value consists of elements of the
              form `pattern:tag'; each string may contain any number  of  such
              specifications separated by spaces.

              The  pattern  is  a pattern that is to be used to generate file-
              names.  Any occurrence of the sequence `%p' is replaced  by  any
              pattern(s) passed by the function calling _files.  Colons in the
              pattern must be preceded by a backslash  to  make  them  distin-
              guishable  from the colon before the tag.  If more than one pat-
              tern is needed, the patterns can be given inside  braces,  sepa-
              rated by commas.

              The  tags  of all strings in the value will be offered by _files
              and used when looking up other styles.  Any  tags  in  the  same
              word  will  be  offered at the same time and before later words.
              If no `:tag' is given the `files' tag will be used.

              The tag may also be followed by an optional second colon  and  a
              description, which will be used for the `%d' in the value of the
              format style (if that is set) instead of the default description
              supplied  by  the completion function.  If the description given
              here contains itself a `%d', that is replaced with the  descrip-
              tion supplied by the completion function.

              For example, to make the rm command first complete only names of
              object files and then the names of all  files  if  there  is  no
              matching object file:

                     zstyle ':completion:*:*:rm:*:*' file-patterns \
                         '*.o:object-files' '%p:all-files'

              To alter the default behaviour of file completion -- offer files
              matching a pattern and directories on the  first  attempt,  then
              all  files -- to offer only matching files on the first attempt,
              then directories, and finally all files:

                     zstyle ':completion:*' file-patterns \
                         '%p:globbed-files' '*(-/):directories' '*:all-files'

              This works even  where  there  is  no  special  pattern:  _files
              matches  all  files  using the pattern `*' at the first step and
              stops when it sees this pattern.  Note also it will never try  a
              pattern more than once for a single completion attempt.

              During  the execution of completion functions, the EXTENDED_GLOB
              option is in effect, so the characters `#',  `~'  and  `^'  have
              special meanings in the patterns.

       file-sort
              The  standard filename completion function uses this style with-
              out a tag to determine  in  which  order  the  names  should  be
              listed;  menu  completion  will  cycle  through them in the same
              order.  The possible values are: `size' to sort by the  size  of
              the  file;  `links'  to sort by the number of links to the file;
              `modification' (or `time' or `date') to sort by the last modifi-
              cation  time;  `access'  to  sort  by  the last access time; and
              `inode' (or `change') to sort by the last inode change time.  If
              the  style is set to any other value, or is unset, files will be
              sorted alphabetically by name.  If the value contains the string
              `reverse',  sorting is done in the opposite order.  If the value
              contains the string `follow', timestamps are associated with the
              targets  of symbolic links; the default is to use the timestamps
              of the links themselves.

       filter The   ldap   plugin   of   email   address    completion    (see
              _email_addresses)  uses  this style to specify the attributes to
              match against when filtering entries.  So for  example,  if  the
              style  is set to `sn', matching is done against surnames.  Stan-
              dard LDAP filtering is used so  normal  completion  matching  is
              bypassed.  If this style is not set, the LDAP plugin is skipped.
              You may also need to set the command style  to  specify  how  to
              connect to your LDAP server.

       force-list
              This forces a list of completions to be shown at any point where
              listing is done, even in cases where the list would  usually  be
              suppressed.   For  example,  normally  the list is only shown if
              there are at least two different matches.  By setting this style
              to  `always',  the  list  will always be shown, even if there is
              only a single match that  will  immediately  be  accepted.   The
              style  may  also be set to a number.  In this case the list will
              be shown if there are at least that many matches, even  if  they
              would all insert the same string.

              This style is tested for the default tag as well as for each tag
              valid for the current completion.   Hence  the  listing  can  be
              forced only for certain types of match.

       format If  this is set for the descriptions tag, its value is used as a
              string to  display  above  matches  in  completion  lists.   The
              sequence  `%d'  in  this  string  will  be replaced with a short
              description of what these matches are.   This  string  may  also
              contain  the following sequences to specify output attributes as
              described in the section EXPANSION OF PROMPT SEQUENCES  in  zsh-
              misc(1): `%B', `%S', `%U', `%F', `%K' and their lower case coun-
              terparts, as well as `%{...%}'.  `%F', `%K' and  `%{...%}'  take
              arguments  in  the same form as prompt expansion.  Note that the
              sequence `%G' is not available; an argument to  `%{'  should  be
              used instead.

              The  style is tested with each tag valid for the current comple-
              tion before it is tested for the descriptions tag.   Hence  dif-
              ferent  format  strings  can  be  defined for different types of
              match.

              Note  also  that  some  completer  functions  define  additional
              `%'-sequences.   These are described for the completer functions
              that make use of them.

              Some completion functions display  messages  that  may  be  cus-
              tomised  by  setting this style for the messages tag.  Here, the
              `%d' is replaced with a message given by  the  completion  func-
              tion.

              Finally,  the  format string is looked up with the warnings tag,
              for use when no matches could be generated at all.  In this case
              the  `%d' is replaced with the descriptions for the matches that
              were  expected  separated  by  spaces.   The  sequence  `%D'  is
              replaced with the same descriptions separated by newlines.

              It  is  possible to use printf-style field width specifiers with
              `%d' and similar escape sequences.  This is handled by the zfor-
              mat  builtin  command  from  the  zsh/zutil  module, see zshmod-
              ules(1).

       glob   This is used by the _expand completer.  If it is set  to  `true'
              (the default), globbing will be attempted on the words resulting
              from a previous substitution (see the substitute style) or  else
              the original string from the line.

       global If  this  is set to `true' (the default), the _expand_alias com-
              pleter and bindable command will try to expand global aliases.

       group-name
              The completion system can  group  different  types  of  matches,
              which  appear in separate lists.  This style can be used to give
              the names of groups for particular tags.  For example,  in  com-
              mand  position  the completion system generates names of builtin
              and external commands, names of  aliases,  shell  functions  and
              parameters  and reserved words as possible completions.  To have
              the external commands and shell functions listed separately:

                     zstyle ':completion:*:*:-command-:*:commands' \
                            group-name commands
                     zstyle ':completion:*:*:-command-:*:functions' \
                            group-name functions

              As a consequence, any match with the same tag will be  displayed
              in the same group.

              If  the  name  given is the empty string the name of the tag for
              the matches will be used as the name of the group.  So, to  have
              all  different  types  of  matches displayed separately, one can
              just set:

                     zstyle ':completion:*' group-name ''

              All matches for which no group name is defined will be put in  a
              group named -default-.

       group-order
              This  style is additional to the group-name style to specify the
              order for display of the groups defined by that  style  (compare
              tag-order,  which  determines  which completions appear at all).
              The groups named are shown in the given order; any other  groups
              are shown in the order defined by the completion function.

              For  example, to have names of builtin commands, shell functions
              and external commands appear in that order  when  completing  in
              command position:

                     zstyle ':completion:*:*:-command-:*:*' group-order \
                            builtins functions commands

       groups A list of names of UNIX groups.  If this is not set, group names
              are taken from the YP database or the file `/etc/group'.

       hidden If this is set to `true', matches for the given context will not
              be listed, although any description for the matches set with the
              format style will be shown.  If it is set to `all', not even the
              description will be displayed.

              Note that the matches will still be completed; they are just not
              shown in the list.  To avoid having matches considered as possi-
              ble  completions  at all, the tag-order style can be modified as
              described below.

       hosts  A list of names of hosts that should be completed.  If  this  is
              not set, hostnames are taken from the file `/etc/hosts'.

       hosts-ports
              This style is used by commands that need or accept hostnames and
              network ports.  The strings in the value should be of  the  form
              `host:port'.   Valid  ports  are  determined  by the presence of
              hostnames; multiple ports for the same host may appear.

       ignore-line
              This is tested for each tag valid for  the  current  completion.
              If  it  is  set to `true', none of the words that are already on
              the line will be considered as possible completions.  If  it  is
              set  to `current', the word the cursor is on will not be consid-
              ered as a possible completion.   The  value  `current-shown'  is
              similar but only applies if the list of completions is currently
              shown on the screen.  Finally, if the style is set  to  `other',
              all  words  on  the  line  except  for  the  current one will be
              excluded from the possible completions.

              The values `current' and `current-shown'  are  a  bit  like  the
              opposite  of  the accept-exact style:  only strings with missing
              characters will be completed.

              Note that you almost certainly don't want to set this to  `true'
              or  `other' for a general context such as `:completion:*'.  This
              is because it would disallow completion of, for example, options
              multiple  times  even  if  the  command  in question accepts the
              option more than once.

       ignore-parents
              The style is tested without a tag  by  the  function  completing
              pathnames  in  order to determine whether to ignore the names of
              directories already mentioned in the current word, or  the  name
              of the current working directory.  The value must include one or
              both of the following strings:

              parent The name of any directory whose path is already contained
                     in  the  word  on the line is ignored.  For example, when
                     completing after foo/../, the directory foo will  not  be
                     considered a valid completion.

              pwd    The  name  of  the  current working directory will not be
                     completed; hence, for example, completion after ../  will
                     not use the name of the current directory.

              In addition, the value may include one or both of:

              ..     Ignore  the  specified  directories only when the word on
                     the line contains the substring `../'.

              directory
                     Ignore the  specified  directories  only  when  names  of
                     directories  are  completed, not when completing names of
                     files.

              Excluded values act in  a  similar  fashion  to  values  of  the
              ignored-patterns style, so they can be restored to consideration
              by the _ignored completer.

       extra-verbose
              If set, the completion listing is more verbose at the cost of  a
              probable  decrease  in completion speed.  Completion performance
              will suffer if this style is set to `true'.

       ignored-patterns
              A list of patterns; any trial completion  matching  one  of  the
              patterns will be excluded from consideration.  The _ignored com-
              pleter can appear in the  list  of  completers  to  restore  the
              ignored  matches.   This  is  a more configurable version of the
              shell parameter $fignore.

              Note that the EXTENDED_GLOB option is set during  the  execution
              of completion functions, so the characters `#', `~' and `^' have
              special meanings in the patterns.

       insert This style is used  by  the  _all_matches  completer  to  decide
              whether  to  insert  the  list  of  all  matches unconditionally
              instead of adding the list as another match.

       insert-ids
              When completing process IDs, for example  as  arguments  to  the
              kill and wait builtins the name of a command may be converted to
              the appropriate process ID.  A problem arises when  the  process
              name  typed  is not unique.  By default (or if this style is set
              explicitly to `menu') the name will be converted immediately  to
              a  set  of  possible IDs, and menu completion will be started to
              cycle through them.

              If the value of the style is `single', the shell will wait until
              the user has typed enough to make the command unique before con-
              verting the name to an ID; attempts at completion will be unsuc-
              cessful  until  that  point.   If the value is any other string,
              menu completion will be started when the  string  typed  by  the
              user is longer than the common prefix to the corresponding IDs.

       insert-tab
              If  this  is  set to `true', the completion system will insert a
              TAB character (assuming  that  was  used  to  start  completion)
              instead  of  performing  completion  when  there is no non-blank
              character to the left of the cursor.  If it is set  to  `false',
              completion will be done even there.

              The  value  may  also contain the substrings `pending' or `pend-
              ing=val'.  In this case, the typed character  will  be  inserted
              instead  of  starting completion when there is unprocessed input
              pending.  If a val is given, completion  will  not  be  done  if
              there  are  at  least that many characters of unprocessed input.
              This is often useful when pasting characters  into  a  terminal.
              Note  however,  that it relies on the $PENDING special parameter
              from the zsh/zle module being set properly which is not  guaran-
              teed on all platforms.

              The  default value of this style is `true' except for completion
              within vared builtin command where it is `false'.

       insert-unambiguous
              This is used by the _match and _approximate  completers.   These
              completers  are  often  used with menu completion since the word
              typed may bear little resemblance to the final completion.  How-
              ever,  if  this  style  is `true', the completer will start menu
              completion only if it could find no unambiguous  initial  string
              at least as long as the original string typed by the user.

              In  the  case of the _approximate completer, the completer field
              in the context will already have been set to one of  correct-num
              or  approximate-num, where num is the number of errors that were
              accepted.

              In the case of the _match completer, the style may also  be  set
              to  the  string `pattern'.  Then the pattern on the line is left
              unchanged if it does not match unambiguously.

       gain-privileges
              If set to true, this style enables the use of commands like sudo
              or doas to gain extra privileges when retrieving information for
              completion. This is only  done  when  a  command  such  as  sudo
              appears  on  the command-line. To force the use of, e.g. sudo or
              to override any prefix that might be added  due  to  gain-privi-
              leges,  the  command  style can be used with a value that begins
              with a hyphen.

       keep-prefix
              This style is used by the _expand completer.  If it  is  `true',
              the  completer  will  try to keep a prefix containing a tilde or
              parameter expansion.  Hence,  for  example,  the  string  `~/f*'
              would  be  expanded  to `~/foo' instead of `/home/user/foo'.  If
              the style is set to `changed' (the  default),  the  prefix  will
              only  be  left unchanged if there were other changes between the
              expanded words and the original word from the command line.  Any
              other value forces the prefix to be expanded unconditionally.

              The  behaviour  of _expand when this style is `true' is to cause
              _expand to give up when a single  expansion  with  the  restored
              prefix  is  the  same  as the original; hence any remaining com-
              pleters may be called.

       last-prompt
              This is a more flexible form of the  ALWAYS_LAST_PROMPT  option.
              If  it  is  `true', the completion system will try to return the
              cursor to the previous command line after displaying  a  comple-
              tion list.  It is tested for all tags valid for the current com-
              pletion, then the default tag.  The cursor will be moved back to
              the  previous  line  if  this  style  is `true' for all types of
              match.  Note that unlike the ALWAYS_LAST_PROMPT option  this  is
              independent of the numeric argument.

       known-hosts-files
              This  style  should  contain  a list of files to search for host
              names and (if the use-ip style is set) IP addresses in a  format
              compatible  with  ssh  known_hosts files.  If it is not set, the
              files /etc/ssh/ssh_known_hosts and ~/.ssh/known_hosts are used.

       list   This style is used by the _history_complete_word  bindable  com-
              mand.  If it is set to `true' it has no effect.  If it is set to
              `false' matches will not be listed.  This overrides the  setting
              of  the  options  controlling  listing  behaviour, in particular
              AUTO_LIST.  The context  always  starts  with  `:completion:his-
              tory-words'.

       list-colors
              If  the zsh/complist module is loaded, this style can be used to
              set color specifications.  This mechanism replaces  the  use  of
              the  ZLS_COLORS and ZLS_COLOURS parameters described in the sec-
              tion `The zsh/complist Module' in zshmodules(1), but the  syntax
              is the same.

              If  this  style  is  set for the default tag, the strings in the
              value are taken as specifications that are  to  be  used  every-
              where.  If it is set for other tags, the specifications are used
              only for matches of the type described by the tag.  For this  to
              work best, the group-name style must be set to an empty string.

              In addition to setting styles for specific tags, it is also pos-
              sible to use group names specified explicitly by the  group-name
              tag together with the `(group)' syntax allowed by the ZLS_COLORS
              and ZLS_COLOURS parameters and simply using the default tag.

              It is possible to use any color specifications  already  set  up
              for the GNU version of the ls command:

                     zstyle ':completion:*:default' list-colors \
                            ${(s.:.)LS_COLORS}

              The  default  colors  are the same as for the GNU ls command and
              can be obtained by setting the style to an  empty  string  (i.e.
              '').

       list-dirs-first
              This is used by file completion.  If set, directories to be com-
              pleted are listed separately  from  and  before  completion  for
              other  files,  regardless of tag ordering.  In addition, the tag
              other-files is used in place  of  all-files  for  the  remaining
              files,  to  indicate that no directories are presented with that
              tag.

       list-grouped
              If this style is `true' (the  default),  the  completion  system
              will  try  to  make  certain completion listings more compact by
              grouping matches.  For example, options for commands  that  have
              the  same  description  (shown  when the verbose style is set to
              `true') will appear as a single entry.  However, menu  selection
              can be used to cycle through all the matches.

       list-packed
              This is tested for each tag valid in the current context as well
              as the default tag.  If it is set to `true',  the  corresponding
              matches  appear  in  listings  as if the LIST_PACKED option were
              set.  If it is set to `false', they are listed normally.

       list-prompt
              If this style is set for the default tag, completion lists  that
              don't  fit on the screen can be scrolled (see the description of
              the zsh/complist module in zshmodules(1)).  The  value,  if  not
              the  empty  string,  will be displayed after every screenful and
              the shell will prompt for a key press; if the style  is  set  to
              the empty string, a default prompt will be used.

              The  value may contain the escape sequences: `%l' or `%L', which
              will be replaced by the number of the last  line  displayed  and
              the total number of lines; `%m' or `%M', the number of the  last
              match shown and the total number of matches; and `%p' and  `%P',
              `Top'  when  at  the beginning of the list, `Bottom' when at the
              end and the position shown as a percentage of the  total  length
              otherwise.  In each case the form with the uppercase letter will
              be replaced by a string of fixed width,  padded  to  the   right
              with  spaces,  while  the  lowercase  form will be replaced by a
              variable width string.  As in other prompt strings,  the  escape
              sequences  `%S',  `%s',  `%B', `%b', `%U', `%u' for entering and
              leaving the display modes  standout,  bold  and  underline,  and
              `%F',  `%f',  `%K',  `%k' for changing the foreground background
              colour, are also available, as is the form `%{...%}' for enclos-
              ing escape sequences which display with zero (or, with a numeric
              argument, some other) width.

              After deleting this prompt the  variable  LISTPROMPT  should  be
              unset for the removal to take effect.

       list-rows-first
              This  style  is  tested in the same way as the list-packed style
              and determines whether matches are to be listed in a  rows-first
              fashion as if the LIST_ROWS_FIRST option were set.

       list-suffixes
              This style is used by the function that completes filenames.  If
              it is `true', and completion is attempted on a string containing
              multiple partially typed pathname components, all ambiguous com-
              ponents will be shown.  Otherwise, completion stops at the first
              ambiguous component.

       list-separator
              The  value  of this style is used in completion listing to sepa-
              rate the string to complete from  a  description  when  possible
              (e.g.  when  completing  options).   It  defaults  to  `--' (two
              hyphens).

       local  This is for use with functions that complete URLs for which  the
              corresponding files are available directly from the file system.
              Its value should consist of three strings: a hostname, the  path
              to  the default web pages for the server, and the directory name
              used by a user placing web pages within their home area.

              For example:

                     zstyle ':completion:*' local toast \
                         /var/http/public/toast public_html

              Completion after `http://toast/stuff/' will look  for  files  in
              the  directory  /var/http/public/toast/stuff,   while completion
              after `http://toast/~yousir/' will look for files in the  direc-
              tory ~yousir/public_html.

       mail-directory
              If  set,  zsh will assume that mailbox files can be found in the
              directory specified.  It defaults to `~/Mail'.

       match-original
              This is used by the _match completer.  If it  is  set  to  only,
              _match  will  try to generate matches without inserting a `*' at
              the cursor position.  If set to any other  non-empty  value,  it
              will first try to generate matches without inserting the `*' and
              if that yields no matches,  it  will  try  again  with  the  `*'
              inserted.   If  it is unset or set to the empty string, matching
              will only be performed with the `*' inserted.

       matcher
              This style is tested separately for each tag valid in  the  cur-
              rent  context.   Its value is placed before any match specifica-
              tions given by the matcher-list style so can override  them  via
              the use of an x: specification.  The value should be in the form
              described in the section `Completion Matching Control'  in  zsh-
              compwid(1).   For  examples  of this, see the description of the
              tag-order style.

       matcher-list
              This style can be set to a list of match specifications that are
              to  be applied everywhere. Match specifications are described in
              the section `Completion Matching Control' in zshcompwid(1).  The
              completion  system will try them one after another for each com-
              pleter selected.  For example, to try  first  simple  completion
              and, if that generates no matches, case-insensitive completion:

                     zstyle ':completion:*' matcher-list '' 'm:{a-zA-Z}={A-Za-z}'

              By  default  each  specification replaces the previous one; how-
              ever, if a specification is prefixed with +, it is added to  the
              existing list.  Hence it is possible to create increasingly gen-
              eral specifications without repetition:

                     zstyle ':completion:*' matcher-list \
                            '' '+m:{a-z}={A-Z}' '+m:{A-Z}={a-z}'

              It is possible to create match specifications valid for particu-
              lar  completers  by  using the third field of the context.  This
              applies  only   to   completers   that   override   the   global
              matcher-list, which as of this writing includes only _prefix and
              _ignored.  For example, to  use  the  completers  _complete  and
              _prefix  but  allow  case-insensitive completion only with _com-
              plete:

                     zstyle ':completion:*' completer _complete _prefix
                     zstyle ':completion:*:complete:*:*:*' matcher-list \
                            '' 'm:{a-zA-Z}={A-Za-z}'

              User-defined names, as explained for the  completer  style,  are
              available.   This  makes  it  possible to try the same completer
              more than once with different match  specifications  each  time.
              For example, to try normal completion without a match specifica-
              tion, then normal  completion  with  case-insensitive  matching,
              then correction, and finally partial-word completion:

                     zstyle ':completion:*' completer \
                         _complete _correct _complete:foo
                     zstyle ':completion:*:complete:*:*:*' matcher-list \
                         '' 'm:{a-zA-Z}={A-Za-z}'
                     zstyle ':completion:*:foo:*:*:*' matcher-list \
                         'm:{a-zA-Z}={A-Za-z} r:|[-_./]=* r:|=*'

              If  the  style is unset in any context no match specification is
              applied.  Note also that some completers such  as  _correct  and
              _approximate  do not use the match specifications at all, though
              these completers will only ever  be  called  once  even  if  the
              matcher-list contains more than one element.

              Where  multiple  specifications are useful, note that the entire
              completion is done for each element of matcher-list,  which  can
              quickly  reduce  the  shell's  performance.   As a rough rule of
              thumb, one to three strings will  give  acceptable  performance.
              On  the other hand, putting multiple space-separated values into
              the same string does not have an appreciable impact  on  perfor-
              mance.

              If  there  is  no current matcher or it is empty, and the option
              NO_CASE_GLOB is in effect, the matching for files  is  performed
              case-insensitively  in  any  case.   However,  any  matcher must
              explicitly  specify  case-insensitive  matching   if   that   is
              required.

       max-errors
              This  is  used  by the _approximate and _correct completer func-
              tions to determine the maximum number of errors to  allow.   The
              completer will try to generate completions by first allowing one
              error, then two errors, and so  on,  until  either  a  match  or
              matches were found or the maximum number of errors given by this
              style has been reached.

              If the value for this style contains the string  `numeric',  the
              completer function will take any numeric argument as the maximum
              number of errors allowed. For example, with

                     zstyle ':completion:*:approximate:::' max-errors 2 numeric

              two errors are allowed if no numeric argument is given, but with
              a  numeric argument of six (as in `ESC-6 TAB'), up to six errors
              are accepted.  Hence with a value of `0 numeric', no  correcting
              completion will be attempted unless a numeric argument is given.

              If  the  value  contains the string `not-numeric', the completer
              will not try to generate  corrected  completions  when  given  a
              numeric  argument,  so  in  this case the number given should be
              greater than zero.  For example, `2 not-numeric' specifies  that
              correcting completion with two errors will usually be performed,
              but if a numeric argument is given, correcting  completion  will
              not be performed.

              The default value for this style is `2 numeric'.

       max-matches-width
              This  style is used to determine the trade off between the width
              of the display used for matches and the  width  used  for  their
              descriptions  when  the  verbose  style is in effect.  The value
              gives the number of display columns to reserve for the  matches.
              The default is half the width of the screen.

              This  has  the  most  impact  when several matches have the same
              description and so will be  grouped  together.   Increasing  the
              style will allow more matches to be grouped together; decreasing
              it will allow more of the description to be visible.

       menu   If this is `true' in the context of any of the tags defined  for
              the  current completion menu completion will be used.  The value
              for a specific tag  will  take  precedence  over  that  for  the
              `default' tag.

              If  none  of the values found in this way is `true' but at least
              one is set to `auto', the shell  behaves  as  if  the  AUTO_MENU
              option is set.

              If  one of the values is explicitly set to `false', menu comple-
              tion will be explicitly turned off, overriding the MENU_COMPLETE
              option and other settings.

              In the form `yes=num', where `yes' may be any of the `true' val-
              ues (`yes', `true', `on'  and  `1'),  menu  completion  will  be
              turned  on  if  there  are  at  least  num matches.  In the form
              `yes=long', menu completion will be turned on if the  list  does
              not  fit  on the screen.  This does not activate menu completion
              if the widget normally only lists completions, but menu  comple-
              tion   can   be   activated   in   that   case  with  the  value
              `yes=long-list'   (Typically,   the   value   `select=long-list'
              described  later  is  more  useful  as  it provides control over
              scrolling.)

              Similarly, with any of the `false' values (as in `no=10'),  menu
              completion will not be used if there are num or more matches.

              The value of this widget also controls menu selection, as imple-
              mented by the zsh/complist module.   The  following  values  may
              appear either alongside or instead of the values above.

              If  the  value contains the string `select', menu selection will
              be started unconditionally.

              In the form `select=num', menu selection will only be started if
              there are at least num matches.  If the values for more than one
              tag provide a number, the smallest number is taken.

              Menu selection can be turned off explicitly by defining a  value
              containing the string`no-select'.

              It  is also possible to start menu selection only if the list of
              matches  does  not  fit  on  the  screen  by  using  the   value
              `select=long'.  To start menu selection even if the current wid-
              get only performs listing, use the value `select=long-list'.

              To turn on menu completion or menu selection when a there are  a
              certain number of matches or the list of matches does not fit on
              the screen, both of `yes=' and `select='  may  be  given  twice,
              once with a number and once with `long' or `long-list'.

              Finally,  it  is  possible to activate two special modes of menu
              selection.  The word `interactive' in the value causes  interac-
              tive  mode  to  be  entered  immediately  when menu selection is
              started; see the description of the zsh/complist module in  zsh-
              modules(1) for a description of interactive mode.  Including the
              string `search' does the same for incremental search  mode.   To
              select   backward   incremental   search,   include  the  string
              `search-backward'.

       muttrc If set, gives the location of the mutt configuration  file.   It
              defaults to `~/.muttrc'.

       numbers
              This is used with the jobs tag.  If it is `true', the shell will
              complete job numbers instead of the shortest unambiguous  prefix
              of  the job command text.  If the value is a number, job numbers
              will only be used if that many words from the  job  descriptions
              are  required to resolve ambiguities.  For example, if the value
              is `1', strings will only be used if  all  jobs  differ  in  the
              first word on their command lines.

       old-list
              This  is  used  by  the  _oldlist  completer.   If  it is set to
              `always', then  standard  widgets  which  perform  listing  will
              retain the current list of matches, however they were generated;
              this can be turned off explicitly with the value `never', giving
              the  behaviour  without the _oldlist completer.  If the style is
              unset, or any other value, then the existing list of completions
              is  displayed if it is not already; otherwise, the standard com-
              pletion list is generated; this  is  the  default  behaviour  of
              _oldlist.   However, if there is an old list and this style con-
              tains the name of the  completer  function  that  generated  the
              list, then the old list will be used even if it was generated by
              a widget which does not do listing.

              For example, suppose you type ^Xc to use the _correct_word  wid-
              get,  which  generates  a list of corrections for the word under
              the cursor.  Usually, typing ^D would generate a  standard  list
              of  completions for the word on the command line, and show that.
              With _oldlist, it will instead  show  the  list  of  corrections
              already generated.

              As  another  example  consider  the  _match  completer: with the
              insert-unambiguous style set to `true' it inserts only a  common
              prefix  string, if there is any.  However, this may remove parts
              of the original pattern, so that further completion  could  pro-
              duce  more  matches  than  on  the  first attempt.  By using the
              _oldlist completer and setting this style to _match, the list of
              matches generated on the first attempt will be used again.

       old-matches
              This  is  used by the _all_matches completer to decide if an old
              list of matches should be used if one exists.  This is  selected
              by  one  of  the  `true' values or by the string `only'.  If the
              value is `only', _all_matches will only  use  an  old  list  and
              won't  have  any  effect  on the list of matches currently being
              generated.

              If this style  is  set  it  is  generally  unwise  to  call  the
              _all_matches completer unconditionally.  One possible use is for
              either this style or the completer style to be defined with  the
              -e option to zstyle to make the style conditional.

       old-menu
              This  is  used  by the _oldlist completer.  It controls how menu
              completion behaves when a completion has already  been  inserted
              and  the  user types a standard completion key such as TAB.  The
              default behaviour of _oldlist is  that  menu  completion  always
              continues  with the existing list of completions.  If this style
              is set to `false', however, a new completion is started  if  the
              old  list  was generated by a different completion command; this
              is the behaviour without the _oldlist completer.

              For example, suppose you type ^Xc to generate a list of  correc-
              tions,  and menu completion is started in one of the usual ways.
              Usually, or with this style set to `false', typing TAB  at  this
              point would start trying to complete the line as it now appears.
              With _oldlist, it instead continues to cycle through the list of
              corrections.

       original
              This  is  used  by  the  _approximate and _correct completers to
              decide if the original string should be added as a possible com-
              pletion.   Normally, this is done only if there are at least two
              possible corrections, but if this style is set to `true', it  is
              always  added.   Note  that  the style will be examined with the
              completer field in  the  context  name  set  to  correct-num  or
              approximate-num,  where  num  is  the number of errors that were
              accepted.

       packageset
              This style is used  when  completing  arguments  of  the  Debian
              `dpkg' program.  It contains an override for the default package
              set for a given context.  For example,

                     zstyle ':completion:*:complete:dpkg:option--status-1:*' \
                                    packageset avail

              causes available packages, rather than only installed  packages,
              to be completed for `dpkg --status'.

       path   The function that completes color names uses this style with the
              colors tag.  The value should be the pathname of a file contain-
              ing  color  names  in the format of an X11 rgb.txt file.  If the
              style is not set but this file is found in one of various  stan-
              dard locations it will be used as the default.

       path-completion
              This  is used by filename completion.  By default, filename com-
              pletion examines all components of a path to see  if  there  are
              completions  of that component.  For example, /u/b/z can be com-
              pleted  to  /usr/bin/zsh.   Explicitly  setting  this  style  to
              `false'  inhibits this behaviour for path components up to the /
              before   the   cursor;   this   overrides   the    setting    of
              accept-exact-dirs.

              Even with the style set to `false', it is still possible to com-
              plete multiple paths by setting the option COMPLETE_IN_WORD  and
              moving  the cursor back to the first component in the path to be
              completed.  For example, /u/b/z can be completed to /usr/bin/zsh
              if the cursor is after the /u.

       pine-directory
              If  set,  specifies the directory containing PINE mailbox files.
              There is no default, since recursively searching this  directory
              is inconvenient for anyone who doesn't use PINE.

       ports  A  list  of  Internet service names (network ports) to complete.
              If this is not set,  service  names  are  taken  from  the  file
              `/etc/services'.

       prefix-hidden
              This  is  used for certain completions which share a common pre-
              fix, for example command options beginning with dashes.   If  it
              is `true', the prefix will not be shown in the list of matches.

              The default value for this style is `false'.

       prefix-needed
              This  style  is  also relevant for matches with a common prefix.
              If it is set to `true' this common prefix must be typed  by  the
              user to generate the matches.

              The  style  is  applicable  to the options, signals, jobs, func-
              tions, and parameters completion tags.

              For command options, this means that the initial  `-',  `+',  or
              `--'  must  be typed explicitly before option names will be com-
              pleted.

              For signals, an initial `-' is required before signal names will
              be completed.

              For  jobs,  an  initial `%' is required before job names will be
              completed.

              For function and parameter names,  an  initial  `_'  or  `.'  is
              required  before function or parameter names starting with those
              characters will be completed.

              The default value for this style is  `false'  for  function  and
              parameter completions, and  `true' otherwise.

       preserve-prefix
              This style is used when completing path names.  Its value should
              be a pattern matching an initial prefix of the word to  complete
              that  should  be  left  unchanged  under all circumstances.  For
              example, on some Unices an initial `//'  (double  slash)  has  a
              special meaning; setting this style to the string `//' will pre-
              serve it.  As another example, setting this style to `?:/' under
              Cygwin would allow completion after `a:/...' and so on.

       range  This  is  used  by  the _history completer and the _history_com-
              plete_word bindable command to decide which words should be com-
              pleted.

              If it is a single number, only the last N words from the history
              will be completed.

              If it is a range of the form `max:slice', the last  slice  words
              will  be  completed;  then  if that yields no matches, the slice
              words before those will be tried and so on.  This process  stops
              either when at least one match has been found, or max words have
              been tried.

              The default is to complete all words from the history at once.

       recursive-files
              If this style is set, its value is an array of  patterns  to  be
              tested  against  `$PWD/':  note the trailing slash, which allows
              directories in the pattern  to  be  delimited  unambiguously  by
              including slashes on both sides.  If an ordinary file completion
              fails and the word on the command  line  does  not  yet  have  a
              directory  part  to  its  name, the style is retrieved using the
              same tag as for the completion just attempted, then the elements
              tested  against  $PWD/  in turn.  If one matches, then the shell
              reattempts completion by prepending the word on the command line
              with  each directory in the expansion of **/*(/) in turn.  Typi-
              cally the elements of the style will be set to restrict the num-
              ber  of directories beneath the current one to a manageable num-
              ber, for example `*/.git/*'.

              For example,

                     zstyle ':completion:*' recursive-files '*/zsh/*'

              If the current directory is  /home/pws/zsh/Src,  then  zle_trTAB
              can be completed to Zle/zle_tricky.c.

       regular
              This  style  is used by the _expand_alias completer and bindable
              command.  If set to `true' (the default), regular  aliases  will
              be  expanded  but  only  in  command  position.  If it is set to
              `false', regular aliases will never be expanded.   If it is  set
              to  `always',  regular  aliases  will be expanded even if not in
              command position.

       rehash If this is set when completing external commands,  the  internal
              list (hash) of commands will be updated for each search by issu-
              ing the rehash command.  There is a speed penalty for this which
              is  only  likely  to  be noticeable when directories in the path
              have slow file access.

       remote-access
              If set to `false', certain commands will be prevented from  mak-
              ing  Internet  connections to retrieve remote information.  This
              includes the completion for the CVS command.

              It is not always possible to know if connections are in fact  to
              a remote site, so some may be prevented unnecessarily.

       remove-all-dups
              The  _history_complete_word  bindable  command  and the _history
              completer use this to decide if all duplicate matches should  be
              removed, rather than just consecutive duplicates.

       select-prompt
              If  this is set for the default tag, its value will be displayed
              during menu selection (see the menu style above) when  the  com-
              pletion  list  does  not fit on the screen as a whole.  The same
              escapes as for the list-prompt style are understood, except that
              the  numbers  refer  to  the  match  or  line the mark is on.  A
              default prompt is used when the value is the empty string.

       select-scroll
              This style is tested for the default tag and  determines  how  a
              completion  list  is  scrolled  during a menu selection (see the
              menu style above) when the completion list does not fit  on  the
              screen  as  a  whole.   If  the value is `0' (zero), the list is
              scrolled by half-screenfuls; if it is a  positive  integer,  the
              list  is scrolled by the given number of lines; if it is a nega-
              tive number, the list is scrolled by a screenful minus the abso-
              lute  value  of  the  given  number of lines.  The default is to
              scroll by single lines.

       separate-sections
              This style is used with the manuals tag when completing names of
              manual  pages.   If it is `true', entries for different sections
              are added separately using tag names  of  the  form  `manual.X',
              where  X  is  the  section number.  When the group-name style is
              also in effect, pages from different sections will appear  sepa-
              rately.   This style is also used similarly with the words style
              when completing words for the dict command. It allows words from
              different  dictionary  databases  to  be  added separately.  The
              default for this style is `false'.

       show-ambiguity
              If the zsh/complist module is loaded, this style can be used  to
              highlight the first ambiguous character in completion lists. The
              value is either a color indication such as  those  supported  by
              the  list-colors  style or, with a value of `true', a default of
              underlining is selected. The highlighting is only applied if the
              completion display strings correspond to the actual matches.

       show-completer
              Tested  whenever a new completer is tried.  If it is `true', the
              completion system outputs a progress message in the listing area
              showing  what  completer  is  being  tried.  The message will be
              overwritten by any output when  completions  are  found  and  is
              removed after completion is finished.

       single-ignored
              This  is  used  by the _ignored completer when there is only one
              match.  If its value is `show', the single match  will  be  dis-
              played  but not inserted.  If the value is `menu', then the sin-
              gle match and the original string are both added as matches  and
              menu  completion  is started, making it easy to select either of
              them.

       sort   Many completion widgets call _description at  some  point  which
              decides  whether the matches are added sorted or unsorted (often
              indirectly via _wanted or _requested).  This style  can  be  set
              explicitly  to  one  of the usual `true' or `false' values as an
              override.  If it is not set for the context, the standard behav-
              iour of the calling widget is used.

              The style is tested first against the full context including the
              tag, and if that fails to produce a value  against  the  context
              without the tag.

              If the calling widget explicitly requests unsorted matches, this
              is usually honoured.  However, the default (unsorted)  behaviour
              of  completion for the command history may be overridden by set-
              ting the style to `true'.

              In the _expand completer, if it is set to `true', the expansions
              generated  will  always be sorted.  If it is set to `menu', then
              the expansions are only sorted when they are offered  as  single
              strings  but  not  in  the string containing all possible expan-
              sions.

       special-dirs
              Normally, the completion code will  not  produce  the  directory
              names  `.'  and  `..' as possible completions.  If this style is
              set to `true', it will add both `.' and `..' as possible comple-
              tions; if it is set to `..', only `..' will be added.

              The following example sets special-dirs to `..' when the current
              prefix is empty, is a single `.', or consists  only  of  a  path
              beginning with `../'.  Otherwise the value is `false'.

                     zstyle -e ':completion:*' special-dirs \
                        '[[ $PREFIX = (../)#(|.|..) ]] && reply=(..)'

       squeeze-slashes
              If  set  to  `true', sequences of slashes in filename paths (for
              example in `foo//bar') will be treated as a single slash.   This
              is  the  usual behaviour of UNIX paths.  However, by default the
              file completion function behaves as if there were a `*'  between
              the slashes.

       stop   If  set  to  `true', the _history_complete_word bindable command
              will stop once when reaching the beginning or end  of  the  his-
              tory.   Invoking _history_complete_word will then wrap around to
              the opposite end of the  history.   If  this  style  is  set  to
              `false'  (the default), _history_complete_word will loop immedi-
              ately as in a menu completion.

       strip-comments
              If set to `true', this style causes non-essential  comment  text
              to  be  removed  from  completion matches.  Currently it is only
              used when completing e-mail addresses where it removes any  dis-
              play  name  from  the  addresses,  cutting  them  down  to plain
              user@host form.

       subst-globs-only
              This is used by the _expand completer.  If it is set to  `true',
              the  expansion  will  only be used if it resulted from globbing;
              hence, if expansions resulted from the  use  of  the  substitute
              style  described  below,  but  these were not further changed by
              globbing, the expansions will be rejected.

              The default for this style is `false'.

       substitute
              This boolean style controls whether the _expand  completer  will
              first  try  to  expand  all substitutions in the string (such as
              `$(...)' and `${...}').

              The default is `true'.

       suffix This is used by the _expand completer if the word starts with  a
              tilde  or  contains  a  parameter  expansion.   If  it is set to
              `true', the word will only be expanded if it doesn't have a suf-
              fix,  i.e.  if it is something like `~foo' or `$foo' rather than
              `~foo/' or `$foo/bar', unless that suffix itself contains  char-
              acters  eligible  for  expansion.  The default for this style is
              `true'.

       tag-order
              This provides a mechanism for sorting how the tags available  in
              a particular context will be used.

              The  values  for  the style are sets of space-separated lists of
              tags.  The tags in each value will be tried at the same time; if
              no  match  is found, the next value is used.  (See the file-pat-
              terns style for an exception to this behavior.)

              For example:

                     zstyle ':completion:*:complete:-command-:*:*' tag-order \
                         'commands functions'

              specifies that  completion  in  command  position  first  offers
              external  commands  and shell functions.  Remaining tags will be
              tried if no completions are found.

              In addition to tag names, each string in the value may take  one
              of the following forms:

              -      If  any  value  consists  of only a hyphen, then only the
                     tags specified in the other values are  generated.   Nor-
                     mally  all tags not explicitly selected are tried last if
                     the specified tags fail to generate  any  matches.   This
                     means  that  a  single  value consisting only of a single
                     hyphen turns off completion.

              ! tags...
                     A string starting  with  an  exclamation  mark  specifies
                     names of tags that are not to be used.  The effect is the
                     same as if all other possible tags for  the  context  had
                     been listed.

              tag:label ...
                     Here,  tag  is  one  of the standard tags and label is an
                     arbitrary name.  Matches are generated as normal but  the
                     name  label  is used in contexts instead of tag.  This is
                     not useful in words starting with !.

                     If the label starts with a hyphen, the tag  is  prepended
                     to  the label to form the name used for lookup.  This can
                     be used to make the completion system try a  certain  tag
                     more  than  once,  supplying different style settings for
                     each attempt; see below for an example.

              tag:label:description
                     As before, but description will replace the `%d'  in  the
                     value of the format style instead of the default descrip-
                     tion supplied by the completion function.  Spaces in  the
                     description  must  be  quoted  with  a backslash.  A `%d'
                     appearing in description is replaced with the description
                     given by the completion function.

              In  any  of  the forms above the tag may be a pattern or several
              patterns in the form `{pat1,pat2...}'.  In this case all  match-
              ing  tags  will  be  used except for any given explicitly in the
              same string.

              One use of these features is to try one tag more than once, set-
              ting  other styles differently on each attempt, but still to use
              all the other tags without having to repeat them all.  For exam-
              ple,  to  make  completion of function names in command position
              ignore all the completion functions starting with an  underscore
              the first time completion is tried:

                     zstyle ':completion:*:*:-command-:*:*' tag-order \
                         'functions:-non-comp *' functions
                     zstyle ':completion:*:functions-non-comp' \
                         ignored-patterns '_*'

              On the first attempt, all tags will be offered but the functions
              tag will be replaced by  functions-non-comp.   The  ignored-pat-
              terns  style  is  set for this tag to exclude functions starting
              with an underscore.  If there are no matches, the  second  value
              of  the  tag-order style is used which completes functions using
              the default tag, this time  presumably  including  all  function
              names.

              The matches for one tag can be split into different groups.  For
              example:

                     zstyle ':completion:*' tag-order \
                         'options:-long:long\ options
                          options:-short:short\ options
                          options:-single-letter:single\ letter\ options'
                     zstyle ':completion:*:options-long' \
                          ignored-patterns '[-+](|-|[^-]*)'
                     zstyle ':completion:*:options-short' \
                          ignored-patterns '--*' '[-+]?'
                     zstyle ':completion:*:options-single-letter' \
                          ignored-patterns '???*'

              With the group-names style set,  options  beginning  with  `--',
              options beginning with a single `-' or `+' but containing multi-
              ple characters, and single-letter options will be  displayed  in
              separate groups with different descriptions.

              Another  use of patterns is to try multiple match specifications
              one after another.  The matcher-list style offers something sim-
              ilar,  but  it is tested very early in the completion system and
              hence can't be set for single commands  nor  for  more  specific
              contexts.   Here  is  how  to  try normal completion without any
              match specification and, if that generates no matches, try again
              with  case-insensitive matching, restricting the effect to argu-
              ments of the command foo:

                     zstyle ':completion:*:*:foo:*:*' tag-order '*' '*:-case'
                     zstyle ':completion:*-case' matcher 'm:{a-z}={A-Z}'

              First, all the tags offered when completing after foo are  tried
              using  the  normal  tag name.  If that generates no matches, the
              second value of tag-order is used, which tries  all  tags  again
              except  that  this  time each has -case appended to its name for
              lookup of styles.  Hence this time the  value  for  the  matcher
              style  from  the second call to zstyle in the example is used to
              make completion case-insensitive.

              It is possible to use the -e option of the zstyle  builtin  com-
              mand  to specify conditions for the use of particular tags.  For
              example:

                     zstyle -e '*:-command-:*' tag-order '
                         if [[ -n $PREFIX$SUFFIX ]]; then
                           reply=( )
                         else
                           reply=( - )
                         fi'

              Completion in command position will be  attempted  only  if  the
              string typed so far is not empty.  This is tested using the PRE-
              FIX special parameter;  see  zshcompwid  for  a  description  of
              parameters which are special inside completion widgets.  Setting
              reply to an empty array provides the default behaviour of trying
              all  tags  at  once;  setting  it  to an array containing only a
              hyphen disables the use of all tags and  hence  of  all  comple-
              tions.

              If  no  tag-order  style  has  been  defined  for a context, the
              strings `(|*-)argument-*  (|*-)option-*  values'  and  `options'
              plus all tags offered by the completion function will be used to
              provide  a  sensible  default  behavior  that  causes  arguments
              (whether normal command arguments or arguments of options) to be
              completed before option names for most commands.

       urls   This is used together with the urls tag by functions  completing
              URLs.

              If  the  value  consists of more than one string, or if the only
              string does not name a file or directory, the strings  are  used
              as the URLs to complete.

              If  the  value  contains  only one string which is the name of a
              normal file the URLs are taken from that file  (where  the  URLs
              may be separated by white space or newlines).

              Finally,  if the only string in the value names a directory, the
              directory hierarchy rooted at this directory gives  the  comple-
              tions.   The  top  level  directory  should  be  the file access
              method, such as `http', `ftp', `bookmark' and so  on.   In  many
              cases  the  next  level  of directories will be a filename.  The
              directory hierarchy can descend as deep as necessary.

              For example,

                     zstyle ':completion:*' urls ~/.urls
                     mkdir -p ~/.urls/ftp/ftp.zsh.org/pub

              allows  completion  of   all   the   components   of   the   URL
              ftp://ftp.zsh.org/pub after suitable commands such as `netscape'
              or `lynx'.  Note, however, that access  methods  and  files  are
              completed  separately, so if the hosts style is set hosts can be
              completed without reference to the urls style.

              See the description in the function _urls itself for more infor-
              mation (e.g. `more $^fpath/_urls(N)').

       use-cache
              If  this  is  set, the completion caching layer is activated for
              any  completions   which   use   it   (via   the   _store_cache,
              _retrieve_cache,  and  _cache_invalid functions).  The directory
              containing the cache files can be changed  with  the  cache-path
              style.

       use-compctl
              If  this style is set to a string not equal to false, 0, no, and
              off, the completion system may use any completion specifications
              defined  with  the  compctl  builtin  command.   If the style is
              unset, this is done only if the zsh/compctl  module  is  loaded.
              The string may also contain the substring `first' to use comple-
              tions defined with `compctl -T', and the substring `default'  to
              use the completion defined with `compctl -D'.

              Note  that  this  is only intended to smooth the transition from
              compctl to the new completion system and may  disappear  in  the
              future.

              Note also that the definitions from compctl will only be used if
              there is no specific completion  function  for  the  command  in
              question.   For example, if there is a function _foo to complete
              arguments to the command foo, compctl will never be invoked  for
              foo.   However,  the  compctl  version will be tried if foo only
              uses default completion.

       use-ip By default, the function _hosts that completes host names strips
              IP  addresses  from entries read from host databases such as NIS
              and ssh files.  If this style is `true',  the  corresponding  IP
              addresses  can  be  completed as well.  This style is not use in
              any context where the hosts style is set; note also it  must  be
              set  before  the cache of host names is generated (typically the
              first completion attempt).

       users  This may be set to a list of usernames to be completed.   If  it
              is  not set all usernames will be completed.  Note that if it is
              set only that list of users will be completed; this  is  because
              on some systems querying all users can take a prohibitive amount
              of time.

       users-hosts
              The values of this style should be of the  form  `user@host'  or
              `user:host'.  It  is  used for commands that need pairs of user-
              and hostnames.  These commands will complete usernames from this
              style  (only),  and will restrict subsequent hostname completion
              to hosts paired with that user in  one  of  the  values  of  the
              style.

              It  is possible to group values for sets of commands which allow
              a remote login, such as rlogin and ssh, by using the my-accounts
              tag.  Similarly, values for sets of commands which usually refer
              to the accounts of other people, such as talk and finger, can be
              grouped  by  using the other-accounts tag.  More ambivalent com-
              mands may use the accounts tag.

       users-hosts-ports
              Like users-hosts but used for commands like telnet and  contain-
              ing strings of the form `user@host:port'.

       verbose
              If set, as it is by default, the completion listing is more ver-
              bose.  In particular many commands show descriptions for options
              if this style is `true'.

       word   This  is  used by the _list completer, which prevents the inser-
              tion of completions until a second completion attempt  when  the
              line has not changed.  The normal way of finding out if the line
              has changed is to compare its entire contents  between  the  two
              occasions.   If  this style is `true', the comparison is instead
              performed only on the current word.  Hence if completion is per-
              formed  on  another word with the same contents, completion will
              not be delayed.

CONTROL FUNCTIONS
       The initialization script compinit redefines all the widgets which per-
       form  completion  to  call the supplied widget function _main_complete.
       This function acts as a wrapper calling the so-called `completer' func-
       tions  that  generate  matches.  If _main_complete is called with argu-
       ments, these are taken as the names of completer functions to be called
       in the order given.  If no arguments are given, the set of functions to
       try is taken from the completer style.  For example, to use normal com-
       pletion and correction if that doesn't generate any matches:

              zstyle ':completion:*' completer _complete _correct

       after  calling compinit. The default value for this style is `_complete
       _ignored', i.e. normally only ordinary completion is tried, first  with
       the  effect  of  the  ignored-patterns  style and then without it.  The
       _main_complete function uses the return status of the  completer  func-
       tions  to  decide  if other completers should be called.  If the return
       status is zero, no other completers are tried  and  the  _main_complete
       function returns.

       If  the  first argument to _main_complete is a single hyphen, the argu-
       ments will not be taken as names of completers.   Instead,  the  second
       argument  gives a name to use in the completer field of the context and
       the other arguments give a command name and arguments to call to gener-
       ate the matches.

       The  following  completer  functions are contained in the distribution,
       although users may write their own.  Note that in contexts the  leading
       underscore  is  stripped,  for example basic completion is performed in
       the context `:completion::complete:...'.

       _all_matches
              This completer can be used to add a  string  consisting  of  all
              other matches.  As it influences later completers it must appear
              as the first completer in the list.  The list of all matches  is
              affected by the avoid-completer and old-matches styles described
              above.

              It may be useful to use the _generic function described below to
              bind _all_matches to its own keystroke, for example:

                     zle -C all-matches complete-word _generic
                     bindkey '^Xa' all-matches
                     zstyle ':completion:all-matches:*' old-matches only
                     zstyle ':completion:all-matches::::' completer _all_matches

              Note  that  this does not generate completions by itself:  first
              use any of the standard ways of generating  a  list  of  comple-
              tions, then use ^Xa to show all matches.  It is possible instead
              to add a standard completer to the list  and  request  that  the
              list of all matches should be directly inserted:

                     zstyle ':completion:all-matches::::' completer \
                            _all_matches _complete
                     zstyle ':completion:all-matches:*' insert true

              In this case the old-matches style should not be set.

       _approximate
              This  is similar to the basic _complete completer but allows the
              completions to  undergo  corrections.   The  maximum  number  of
              errors  can  be  specified  by  the  max-errors  style;  see the
              description of approximate matching in zshexpn(1) for how errors
              are  counted.   Normally this completer will only be tried after
              the normal _complete completer:

                     zstyle ':completion:*' completer _complete _approximate

              This will give correcting completion if and only if normal  com-
              pletion  yields no possible completions.  When corrected comple-
              tions are found, the completer will normally start menu  comple-
              tion allowing you to cycle through these strings.

              This  completer uses the tags corrections and original when gen-
              erating the possible corrections and the original  string.   The
              format style for the former may contain the additional sequences
              `%e' and `%o' which will be replaced by  the  number  of  errors
              accepted  to  generate  the corrections and the original string,
              respectively.

              The completer  progressively  increases  the  number  of  errors
              allowed up to the limit by the max-errors style, hence if a com-
              pletion is found with one error, no completions with two  errors
              will be shown, and so on.  It modifies the completer name in the
              context to indicate the number of errors  being  tried:  on  the
              first  try  the completer field contains `approximate-1', on the
              second try `approximate-2', and so on.

              When _approximate is called from another function, the number of
              errors to accept may be passed with the -a option.  The argument
              is in the same format  as  the  max-errors  style,  all  in  one
              string.

              Note  that  this completer (and the _correct completer mentioned
              below) can be quite expensive to call, especially when  a  large
              number  of  errors are allowed.  One way to avoid this is to set
              up the completer style using the -e option  to  zstyle  so  that
              some  completers  are  only  used when completion is attempted a
              second time on the same string, e.g.:

                     zstyle -e ':completion:*' completer '
                       if [[ $_last_try != "$HISTNO$BUFFER$CURSOR" ]]; then
                         _last_try="$HISTNO$BUFFER$CURSOR"
                         reply=(_complete _match _prefix)
                       else
                         reply=(_ignored _correct _approximate)
                       fi'

              This uses the HISTNO parameter and the BUFFER and CURSOR special
              parameters  that are available inside zle and completion widgets
              to find out if the command line hasn't changed  since  the  last
              time completion was tried.  Only then are the _ignored, _correct
              and _approximate completers called.

       _canonical_paths [ -A var ] [ -N ] [ -MJV12nfX ] tag descr [ paths  ...
       ]
              This  completion  function  completes all paths given to it, and
              also tries to offer completions which point to the same file  as
              one  of  the paths given (relative path when an absolute path is
              given, and vice versa; when ..'s are present in the word  to  be
              completed; and some paths got from symlinks).

              -A, if specified, takes the paths from the array variable speci-
              fied. Paths can also be specified on the command line  as  shown
              above.   -N,  if  specified,  prevents  canonicalizing the paths
              given before using them for completion, in case they are already
              so.  The  options  -M,  -J, -V, -1, -2, -n, -F, -X are passed to
              compadd.

              See _description for a description of tag and descr.

       _complete
              This completer generates all  possible  completions  in  a  con-
              text-sensitive  manner, i.e. using the settings defined with the
              compdef function explained above and the current settings of all
              special parameters.  This gives the normal completion behaviour.

              To  complete  arguments  of commands, _complete uses the utility
              function _normal, which is in turn responsible for  finding  the
              particular function; it is described below.  Various contexts of
              the form -context- are handled specifically. These are all  men-
              tioned above as possible arguments to the #compdef tag.

              Before  trying  to find a function for a specific context, _com-
              plete checks if the  parameter  `compcontext'  is  set.  Setting
              `compcontext'  allows  the  usual  completion  dispatching to be
              overridden which is useful in places such  as  a  function  that
              uses vared for input. If it is set to an array, the elements are
              taken to be the possible matches which will be  completed  using
              the tag `values' and the description `value'. If it is set to an
              associative array, the keys are used as the possible completions
              and  the  values (if non-empty) are used as descriptions for the
              matches.  If `compcontext' is set to a string containing colons,
              it  should  be of the form `tag:descr:action'.  In this case the
              tag and descr give the tag and description to use and the action
              indicates  what should be completed in one of the forms accepted
              by the _arguments utility function described below.

              Finally, if `compcontext' is set to a string without colons, the
              value  is  taken as the name of the context to use and the func-
              tion defined for that context will be called.  For this purpose,
              there  is  a special context named -command-line- that completes
              whole command lines (commands and their arguments).  This is not
              used  by the completion system itself but is nonetheless handled
              when explicitly called.

       _correct
              Generate corrections, but not completions, for the current word;
              this is similar to _approximate but will not allow any number of
              extra characters at the cursor  as  that  completer  does.   The
              effect  is  similar to spell-checking.  It is based on _approxi-
              mate, but the completer field in the context name is correct.

              For example, with:

                     zstyle ':completion:::::' completer \
                            _complete _correct _approximate
                     zstyle ':completion:*:correct:::' max-errors 2 not-numeric
                     zstyle ':completion:*:approximate:::' max-errors 3 numeric

              correction will accept up to two errors.  If a numeric  argument
              is  given, correction will not be performed, but correcting com-
              pletion will be, and will accept as many errors as given by  the
              numeric  argument.  Without a numeric argument, first correction
              and then correcting completion will be tried, with the first one
              accepting two errors and the second one accepting three errors.

              When  _correct  is called as a function, the number of errors to
              accept may be given following the -a option.  The argument is in
              the same form a values to the accept style, all in one string.

              This  completer  function  is  intended  to  be used without the
              _approximate completer or, as in the example,  just  before  it.
              Using  it  after  the  _approximate  completer  is useless since
              _approximate will at least generate the corrected strings gener-
              ated by the _correct completer -- and probably more.

       _expand
              This  completer function does not really perform completion, but
              instead checks if the word on the command line is  eligible  for
              expansion  and,  if  it is, gives detailed control over how this
              expansion is done.  For this to happen,  the  completion  system
              needs  to  be invoked with complete-word, not expand-or-complete
              (the default binding for TAB), as otherwise the string  will  be
              expanded by the shell's internal mechanism before the completion
              system is started.  Note also this completer  should  be  called
              before the _complete completer function.

              The  tags used when generating expansions are all-expansions for
              the string containing all possible expansions,  expansions  when
              adding  the  possible  expansions as single matches and original
              when adding the original string from the  line.   The  order  in
              which  these strings are generated, if at all, can be controlled
              by the group-order and tag-order styles, as usual.

              The format string for all-expansions and for expansions may con-
              tain  the  sequence  `%o' which will be replaced by the original
              string from the line.

              The kind of expansion to be tried is controlled by  the  substi-
              tute, glob and subst-globs-only styles.

              It is also possible to call _expand as a function, in which case
              the different modes may be selected with options: -s for substi-
              tute, -g for glob and -o for subst-globs-only.

       _expand_alias
              If  the word the cursor is on is an alias, it is expanded and no
              other completers are called.  The types of aliases which are  to
              be  expanded  can  be controlled with the styles regular, global
              and disabled.

              This function is also a bindable command, see the section `Bind-
              able Commands' below.

       _extensions
              If  the  cursor follows the string `*.', filename extensions are
              completed. The extensions are taken from files in current direc-
              tory  or  a  directory specified at the beginning of the current
              word. For exact matches, completion  continues  to  allow  other
              completers  such  as _expand to expand the pattern. The standard
              add-space and prefix-hidden styles are observed.

       _external_pwds
              Completes current directories of other zsh  processes  belonging
              to the current user.

              This  is intended to be used via _generic, bound to a custom key
              combination. Note that pattern matching is enabled  so  matching
              is performed similar to how it works with the _match completer.

       _history
              Complete  words  from  the  shell's command  history.  This com-
              pleter can be controlled by the remove-all-dups, and sort styles
              as for the _history_complete_word bindable command, see the sec-
              tion `Bindable Commands' below and the section `Completion  Sys-
              tem Configuration' above.

       _ignored
              The  ignored-patterns  style  can  be  set to a list of patterns
              which are compared against possible completions;  matching  ones
              are  removed.   With  this  completer those matches can be rein-
              stated, as if no ignored-patterns style were set.  The completer
              actually generates its own list of matches; which completers are
              invoked is determined in the same way as for  the  _prefix  com-
              pleter.  The single-ignored style is also available as described
              above.

       _list  This completer allows the insertion of  matches  to  be  delayed
              until  completion is attempted a second time without the word on
              the line being changed.  On the first attempt, only the list  of
              matches  will  be shown.  It is affected by the styles condition
              and word, see  the  section  `Completion  System  Configuration'
              above.

       _match This  completer  is intended to be used after the _complete com-
              pleter.  It behaves similarly but the string on the command line
              may be a pattern to match against trial completions.  This gives
              the effect of the GLOB_COMPLETE option.

              Normally completion will be performed by taking the pattern from
              the  line,  inserting a `*' at the cursor position and comparing
              the resulting pattern with the possible  completions  generated.
              This  can  be  modified  with the match-original style described
              above.

              The generated matches will  be  offered  in  a  menu  completion
              unless  the  insert-unambiguous  style is set to `true'; see the
              description above for other options for this style.

              Note that matcher specifications defined globally or used by the
              completion  functions (the styles matcher-list and matcher) will
              not be used.

       _menu  This completer was written as simple example  function  to  show
              how  menu  completion  can be enabled in shell code. However, it
              has the notable effect of disabling menu selection which can  be
              useful  with  _generic  based  widgets. It should be used as the
              first completer in the list.  Note that this is  independent  of
              the  setting  of the MENU_COMPLETE option and does not work with
              the other menu completion widgets such as reverse-menu-complete,
              or accept-and-menu-complete.

       _oldlist
              This  completer  controls  how  the  standard completion widgets
              behave when there is an existing list of completions  which  may
              have  been  generated  by  a  special  completion  (i.e. a sepa-
              rately-bound completion command).  It allows the  ordinary  com-
              pletion  keys  to  continue  to use the list of completions thus
              generated, instead of producing a new list of  ordinary  contex-
              tual  completions.   It  should appear in the list of completers
              before any of the widgets which generate matches.  It  uses  two
              styles:  old-list and old-menu, see the section `Completion Sys-
              tem Configuration' above.

       _prefix
              This completer can be used to try  completion  with  the  suffix
              (everything after the cursor) ignored.  In other words, the suf-
              fix will not be considered to be part of the word  to  complete.
              The effect is similar to the expand-or-complete-prefix command.

              The completer style is used to decide which other completers are
              to be called to generate matches.  If this style is  unset,  the
              list  of  completers  set  for  the  current  context is used --
              except, of course, the _prefix completer  itself.   Furthermore,
              if  this  completer  appears  more than once in the list of com-
              pleters only those completers not  already  tried  by  the  last
              invocation of _prefix will be called.

              For example, consider this global completer style:

                     zstyle ':completion:*' completer \
                         _complete _prefix _correct _prefix:foo

              Here, the _prefix completer tries normal completion but ignoring
              the suffix.  If that doesn't generate any matches,  and  neither
              does  the  call to the _correct completer after it, _prefix will
              be called a second time and, now only trying correction with the
              suffix  ignored.  On the second invocation the completer part of
              the context appears as `foo'.

              To use _prefix as the last resort and try only normal completion
              when it is invoked:

                     zstyle ':completion:*' completer _complete ... _prefix
                     zstyle ':completion::prefix:*' completer _complete

              The  add-space  style is also respected.  If it is set to `true'
              then _prefix will insert a space between the  matches  generated
              (if any) and the suffix.

              Note  that this completer is only useful if the COMPLETE_IN_WORD
              option is set; otherwise, the cursor will be moved to the end of
              the  current word before the completion code is called and hence
              there will be no suffix.

       _user_expand
              This completer behaves similarly to the  _expand  completer  but
              instead  performs  expansions  defined  by  users.   The  styles
              add-space and sort styles specific to the _expand completer  are
              usable  with  _user_expand  in  addition to other styles handled
              more generally by the completion system.  The tag all-expansions
              is also available.

              The  expansion  depends  on  the  array  style user-expand being
              defined for the current context; remember that the  context  for
              completers  is less specific than that for contextual completion
              as the full context has not yet been  determined.   Elements  of
              the array may have one of the following forms:

              $hash

                     hash  is  the name of an associative array.  Note this is
                     not a full parameter expression,  merely  a  $,  suitably
                     quoted  to  prevent  immediate expansion, followed by the
                     name of an associative array.   If  the  trial  expansion
                     word  matches  a  key in hash, the resulting expansion is
                     the corresponding value.
              _func

                     _func is the name of a shell  function  whose  name  must
                     begin  with _ but is not otherwise special to the comple-
                     tion system.  The function is called with the trial  word
                     as an argument.  If the word is to be expanded, the func-
                     tion should set the array reply to a list of  expansions.
                     Optionally,  it can set REPLY to a word that will be used
                     as a description for the set of expansions.   The  return
                     status of the function is irrelevant.
BINDABLE COMMANDS
       In  addition  to  the context-dependent completions provided, which are
       expected to work in an intuitively obvious way, there are a few widgets
       implementing  special  behaviour which can be bound separately to keys.
       The following is a list of these and their default bindings.

       _bash_completions
              This function is used by two  widgets,  _bash_complete-word  and
              _bash_list-choices.   It  exists  to  provide compatibility with
              completion bindings in bash.  The last character of the  binding
              determines  what is completed: `!', command names; `$', environ-
              ment variables; `@', host  names;  `/',  file  names;  `~'  user
              names.   In bash, the binding preceded by `\e' gives completion,
              and preceded by `^X' lists options.  As some of  these  bindings
              clash with standard zsh bindings, only `\e~' and `^X~' are bound
              by default.  To add the rest, the following should be  added  to
              .zshrc after compinit has been run:

                     for key in '!' '$' '@' '/' '~'; do
                       bindkey "\e$key" _bash_complete-word
                       bindkey "^X$key" _bash_list-choices
                     done

              This  includes  the  bindings  for `~' in case they were already
              bound to something else; the completion code does  not  override
              user bindings.

       _correct_filename (^XC)
              Correct  the filename path at the cursor position.  Allows up to
              six errors in the name.  Can also be called with an argument  to
              correct a filename path, independently of zle; the correction is
              printed on standard output.

       _correct_word (^Xc)
              Performs correction of the current argument using the usual con-
              textual  completions as possible choices. This stores the string
              `correct-word' in the function field of  the  context  name  and
              then calls the _correct completer.

       _expand_alias (^Xa)
              This  function can be used as a completer and as a bindable com-
              mand.  It expands the word the cursor is on if it is  an  alias.
              The  types  of  alias expanded can be controlled with the styles
              regular, global and disabled.

              When used as a bindable command there is one additional  feature
              that  can  be  selected by setting the complete style to `true'.
              In this case,  if  the  word  is  not  the  name  of  an  alias,
              _expand_alias  tries  to  complete the word to a full alias name
              without expanding it.  It leaves the cursor directly  after  the
              completed  word  so  that  invoking _expand_alias once more will
              expand the now-complete alias name.

       _expand_word (^Xe)
              Performs expansion on the current word:  equivalent to the stan-
              dard  expand-word  command,  but  using  the  _expand completer.
              Before calling it, the function field of the context is  set  to
              `expand-word'.

       _generic
              This  function  is  not  defined  as  a  widget and not bound by
              default.  However, it can be used to define a  widget  and  will
              then  store  the name of the widget in the function field of the
              context and call the completion system.  This allows custom com-
              pletion  widgets  with  their  own  set  of style settings to be
              defined easily.  For example, to define a widget  that  performs
              normal completion and starts menu selection:

                     zle -C foo complete-word _generic
                     bindkey '...' foo
                     zstyle ':completion:foo:*' menu yes select=1

              Note  in  particular that the completer style may be set for the
              context in order to change the set of functions used to generate
              possible  matches.   If _generic is called with arguments, those
              are passed through to _main_complete as the list  of  completers
              in place of those defined by the completer style.

       _history_complete_word (\e/)
              Complete  words  from the shell's command history. This uses the
              list, remove-all-dups, sort, and stop styles.

       _most_recent_file (^Xm)
              Complete the name of the most recently  modified  file  matching
              the  pattern on the command line (which may be blank).  If given
              a numeric argument N, complete the Nth  most  recently  modified
              file.  Note the completion, if any, is always unique.

       _next_tags (^Xn)
              This command alters the set of matches used to that for the next
              tag, or set of tags, either as given by the tag-order  style  or
              as  set  by default; these matches would otherwise not be avail-
              able.  Successive invocations of the command cycle  through  all
              possible sets of tags.

       _read_comp (^X^R)
              Prompt the user for a string, and use that to perform completion
              on the current  word.   There  are  two  possibilities  for  the
              string.   First,  it  can  be  a set of words beginning `_', for
              example `_files -/', in which case the function with  any  argu-
              ments  will  be called to generate the completions.  Unambiguous
              parts of the function name will be completed automatically (nor-
              mal  completion is not available at this point) until a space is
              typed.

              Second, any other string will be passed as a set of arguments to
              compadd and should hence be an expression specifying what should
              be completed.

              A very restricted set of  editing  commands  is  available  when
              reading  the  string:  `DEL' and `^H' delete the last character;
              `^U' deletes the line, and `^C' and  `^G'  abort  the  function,
              while  `RET'  accepts  the  completion.  Note the string is used
              verbatim as a command line,  so  arguments  must  be  quoted  in
              accordance with standard shell rules.

              Once  a  string  has been read, the next call to _read_comp will
              use the existing string instead of reading a new one.  To  force
              a  new  string  to be read, call _read_comp with a numeric argu-
              ment.

       _complete_debug (^X?)
              This widget performs ordinary completion, but captures in a tem-
              porary  file  a trace of the shell commands executed by the com-
              pletion system.  Each completion attempt gets its own  file.   A
              command  to  view  each of these files is pushed onto the editor
              buffer stack.

       _complete_help (^Xh)
              This widget displays information about the  context  names,  the
              tags,  and  the completion functions used when completing at the
              current cursor position. If given a numeric argument other  than
              1 (as in `ESC-2 ^Xh'), then the styles used and the contexts for
              which they are used will be shown, too.

              Note that the information about styles  may  be  incomplete;  it
              depends  on  the information available from the completion func-
              tions called, which in turn is  determined  by  the  user's  own
              styles and other settings.

       _complete_help_generic
              Unlike  other  commands  listed  here, this must be created as a
              normal ZLE widget rather than a completion widget (i.e. with zle
              -N).   It is used for generating help with a widget bound to the
              _generic widget that is described above.

              If this widget is created using the name of the function, as  it
              is  by  default, then when executed it will read a key sequence.
              This is expected to be bound to a call to a completion  function
              that  uses  the  _generic widget.  That widget will be executed,
              and information provided in  the  same  format  that  the  _com-
              plete_help widget displays for contextual completion.

              If  the  widget's name contains debug, for example if it is cre-
              ated as `zle -N _complete_debug_generic _complete_help_generic',
              it  will  read and execute the keystring for a generic widget as
              before, but then generate debugging information as done by _com-
              plete_debug for contextual completion.

              If  the  widget's  name  contains  noread,  it  will  not read a
              keystring but instead arrange that the next  use  of  a  generic
              widget  run  in the same shell will have the effect as described
              above.

              The   widget   works   by   setting    the    shell    parameter
              ZSH_TRACE_GENERIC_WIDGET  which  is read by _generic.  Unsetting
              the parameter cancels any pending effect of the noread form.

              For example, after executing the following:

                     zle -N _complete_debug_generic _complete_help_generic
                     bindkey '^x:' _complete_debug_generic

              typing `C-x :' followed by the key sequence for a generic widget
              will cause trace output for that widget to be saved to a file.

       _complete_tag (^Xt)
              This  widget completes symbol tags created by the etags or ctags
              programmes (note there is no connection with the completion sys-
              tem's  tags) stored in a file TAGS, in the format used by etags,
              or tags, in the format created by ctags.  It will look  back  up
              the  path  hierarchy for the first occurrence of either file; if
              both exist, the file TAGS is preferred.   You  can  specify  the
              full path to a TAGS or tags file by setting the parameter $TAGS-
              FILE or $tagsfile respectively.   The  corresponding  completion
              tags used are etags and vtags, after emacs and vi respectively.

UTILITY FUNCTIONS
       Descriptions follow for utility functions that may be useful when writ-
       ing completion functions.  If functions are  installed  in  subdirecto-
       ries,  most of these reside in the Base subdirectory.  Like the example
       functions for commands in the distribution, the utility functions  gen-
       erating  matches  all follow the convention of returning status zero if
       they generated completions and  non-zero  if  no  matching  completions
       could be added.

       _absolute_command_paths
              This  function  completes  external  commands  as absolute paths
              (unlike _command_names -e which completes their basenames).   It
              takes no arguments.

       _all_labels [ -x ] [ -12VJ ] tag name descr [ command arg ... ]
              This  is  a  convenient  interface  to  the _next_label function
              below, implementing the loop shown in the  _next_label  example.
              The  command  and  its  arguments  are  called  to  generate the
              matches.  The options stored in the parameter name will automat-
              ically  be  inserted  into the args passed to the command.  Nor-
              mally, they are put directly after the command, but  if  one  of
              the  args  is a single hyphen, they are inserted directly before
              that.  If the hyphen is the last argument, it  will  be  removed
              from  the  argument  list  before  the  command is called.  This
              allows _all_labels to be used in  almost  all  cases  where  the
              matches can be generated by a single call to the compadd builtin
              command or by a call to one of the utility functions.

              For example:

                     local expl
                     ...
                     if _requested foo; then
                       ...
                       _all_labels foo expl '...' compadd ... - $matches
                     fi

              Will complete the strings from the matches parameter, using com-
              padd  with  additional  options  which will take precedence over
              those generated by _all_labels.

       _alternative [ -O name ] [ -C name ] spec ...
              This function is useful in simple cases where multiple tags  are
              available.   Essentially  it  implements  a  loop  like  the one
              described for the _tags function below.

              The tags to use and the action to perform if a tag is  requested
              are   described   using   the  specs  which  are  of  the  form:
              `tag:descr:action'.  The tags are offered using _tags and if the
              tag is requested, the action is executed with the given descrip-
              tion descr.  The actions are those accepted  by  the  _arguments
              function  (described  below), excluding the `->state' and `=...'
              forms.

              For example, the action may be a simple function call:

                     _alternative \
                         'users:user:_users' \
                         'hosts:host:_hosts'

              offers usernames and hostnames as possible matches, generated by
              the _users and _hosts functions respectively.

              Like  _arguments,  this function uses _all_labels to execute the
              actions, which will loop over all sets of  tags.   Special  han-
              dling  is only required if there is an additional valid tag, for
              example inside a function called from _alternative.

              The option `-O name' is used in the same way as  by  the  _argu-
              ments  function.  In other words, the elements of the name array
              will be passed to compadd when executing an action.

              Like _tags this function supports the -C option to give  a  dif-
              ferent name for the argument context field.


       _arguments [ -nswWCRS ] [ -A pat ] [ -O name ] [ -M matchspec ]
                  [ : ] spec ...
       _arguments [ opt ... ] -- [ -i pats ] [ -s pair ] [ helpspec ... ]
              This  function  can be used to give a complete specification for
              completion for a command whose arguments  follow  standard  UNIX
              option and argument conventions.

              Options overview

              Options  to _arguments itself must be in separate words, i.e. -s
              -w, not -sw.  The options are followed by  specs  that  describe
              options  and  arguments  of  the  analyzed  command.  specs that
              describe  option  flags  must  precede   specs   that   describe
              non-option  ("positional" or "normal") arguments of the analyzed
              line.  To avoid ambiguity, all options to _arguments itself  may
              be separated from the spec forms by a single colon.

              The  `--' form is used to intuit spec forms from the help output
              of the command being analyzed, and is described in detail below.
              The opts for the `--' form are otherwise the same options as the
              first form.  Note that `-s' following `--' has a distinct  mean-
              ing from `-s' preceding `--', and both may appear.

              The option switches -s, -S, -A, -w, and -W affect how _arguments
              parses the analyzed command line's options.  These switches  are
              useful for commands with standard argument parsing.

              The options of _arguments have the following meanings:

              -n     With  this  option, _arguments sets the parameter NORMARG
                     to the position of  the  first  normal  argument  in  the
                     $words  array,  i.e.  the  position  after the end of the
                     options.  If that argument has not been reached,  NORMARG
                     is  set  to  -1.  The caller should declare `integer NOR-
                     MARG' if the -n option is passed; otherwise the parameter
                     is not used.

              -s     Enable option stacking for single-letter options, whereby
                     multiple single-letter options may  be  combined  into  a
                     single  word.  For example, the two options `-x' and `-y'
                     may be combined into a single word  `-xy'.   By  default,
                     every  word corresponds to a single option name (`-xy' is
                     a single option named `xy').

                     Options beginning with a single hyphen or plus  sign  are
                     eligible  for  stacking; words beginning with two hyphens
                     are not.

                     Note that -s after -- has a different meaning,  which  is
                     documented  in  the segment entitled `Deriving spec forms
                     from the help output'.

              -w     In combination with -s, allow option stacking even if one
                     or  more  of the options take arguments.  For example, if
                     -x takes an argument, with no -s, `-xy' is considered  as
                     a  single  (unhandled)  option; with -s, -xy is an option
                     with the argument `y'; with both -s and -w,  -xy  is  the
                     option  -x and the option -y with arguments to -x (and to
                     -y, if it takes arguments) still to  come  in  subsequent
                     words.

              -W     This  option takes -w a stage further:  it is possible to
                     complete single-letter options  even  after  an  argument
                     that occurs in the same word.  However, it depends on the
                     action performed whether options will really be completed
                     at  this point.  For more control, use a utility function
                     like _guard as part of the action.

              -C     Modify the curcontext parameter for an action of the form
                     `->state'.  This is discussed in detail below.

              -R     Return  status 300 instead of zero when a $state is to be
                     handled, in the `->string' syntax.

              -S     Do not complete options after a  `--'  appearing  on  the
                     line,  and ignore the `--'.  For example, with -S, in the
                     line

                            foobar -x -- -y

                     the `-x' is considered an option, the `-y' is  considered
                     an argument, and the `--' is considered to be neither.

              -A pat Do  not complete options after the first non-option argu-
                     ment on the line.  pat is a pattern matching all  strings
                     which  are not to be taken as arguments.  For example, to
                     make _arguments stop completing options after  the  first
                     normal argument, but ignoring all strings starting with a
                     hyphen even if they are not described by one of the  opt-
                     specs, the form is `-A "-*"'.

              -O name
                     Pass the elements of the array name as arguments to func-
                     tions called to execute actions.  This  is  discussed  in
                     detail below.

              -M matchspec
                     Use  the  match  specification  matchspec  for completing
                     option names and values.  The  default  matchspec  allows
                     partial  word  completion after `_' and `-', such as com-
                     pleting `-f-b' to `-foo-bar'.  The default matchspec is:
                     r:|[_-]=* r:|=*

              specs: overview

              Each of the following forms is a spec describing individual sets
              of options or arguments on the command line being analyzed.

              n:message:action
              n::message:action
                     This  describes  the  n'th  normal argument.  The message
                     will be printed  above  the  matches  generated  and  the
                     action  indicates  what can be completed in this position
                     (see below).  If there are two colons before the  message
                     the  argument  is optional.  If the message contains only
                     white space, nothing will be printed  above  the  matches
                     unless the action adds an explanation string itself.

              :message:action
              ::message:action
                     Similar, but describes the next argument, whatever number
                     that happens to be.  If all arguments  are  specified  in
                     this  form  in the correct order the numbers are unneces-
                     sary.

              *:message:action
              *::message:action
              *:::message:action
                     This describes how arguments  (usually  non-option  argu-
                     ments,  those  not  beginning with - or +) are to be com-
                     pleted when neither of the first two forms was  provided.
                     Any number of arguments can be completed in this fashion.

                     With  two  colons  before  the message, the words special
                     array and the CURRENT special parameter are  modified  to
                     refer  only  to  the  normal arguments when the action is
                     executed or evaluated.  With three colons before the mes-
                     sage  they are modified to refer only to the normal argu-
                     ments covered by this description.

              optspec
              optspec:...
                     This describes an option.  The colon  indicates  handling
                     for  one  or  more  arguments to the option; if it is not
                     present, the option is assumed to take no arguments.

                     The following forms are available for  the  initial  opt-
                     spec, whether or not the option has arguments.

                     *optspec
                            Here  optspec is one of the remaining forms below.
                            This  indicates  the  following  optspec  may   be
                            repeated.   Otherwise  if the corresponding option
                            is already present on the command line to the left
                            of the cursor it will not be offered again.

                     -optname
                     +optname
                            In  the  simplest  form  the  optspec  is just the
                            option name beginning with a minus or a plus sign,
                            such as `-foo'.  The first argument for the option
                            (if any) must follow as a separate  word  directly
                            after the option.

                            Either  of `-+optname' and `+-optname' can be used
                            to specify that -optname  and  +optname  are  both
                            valid.

                            In all the remaining forms, the leading `-' may be
                            replaced by or paired with `+' in this way.

                     -optname-
                            The  first  argument  of  the  option  must   come
                            directly  after  the option name in the same word.
                            For example, `-foo-:...' specifies that  the  com-
                            pleted   option   and   argument  will  look  like
                            `-fooarg'.

                     -optname+
                            The first argument may  appear  immediately  after
                            optname in the same word, or may appear as a sepa-
                            rate  word  after  the   option.    For   example,
                            `-foo+:...'  specifies  that  the completed option
                            and argument will look like  either  `-fooarg'  or
                            `-foo arg'.

                     -optname=
                            The  argument  may  appear as the next word, or in
                            same word as the option name provided that  it  is
                            separated  from  it by an equals sign, for example
                            `-foo=arg' or `-foo arg'.

                     -optname=-
                            The argument to the option must  appear  after  an
                            equals sign in the same word, and may not be given
                            in the next argument.

                     optspec[explanation]
                            An explanation string may be appended  to  any  of
                            the  preceding forms of optspec by enclosing it in
                            brackets, as in `-q[query operation]'.

                            The verbose style is used to  decide  whether  the
                            explanation  strings are displayed with the option
                            in a completion listing.

                            If no bracketed explanation string  is  given  but
                            the  auto-description  style  is  set and only one
                            argument is described for this optspec, the  value
                            of  the style is displayed, with any appearance of
                            the sequence `%d' in it replaced by the message of
                            the  first  optarg  that  follows the optspec; see
                            below.

                     It is possible for options with a literal `+' or  `='  to
                     appear,  but  that  character must be quoted, for example
                     `-\+'.

                     Each optarg following an optspec must  take  one  of  the
                     following forms:

                     :message:action
                     ::message:action
                            An  argument to the option; message and action are
                            treated as for ordinary arguments.  In  the  first
                            form, the argument is mandatory, and in the second
                            form it is optional.

                            This group may be repeated for options which  take
                            multiple   arguments.    In   other  words,  :mes-
                            sage1:action1:message2:action2 specifies that  the
                            option takes two arguments.

                     :*pattern:message:action
                     :*pattern::message:action
                     :*pattern:::message:action
                            This  describes multiple arguments.  Only the last
                            optarg for an option taking multiple arguments may
                            be  given  in  this form.  If the pattern is empty
                            (i.e. :*:), all the remaining words  on  the  line
                            are  to  be  completed as described by the action;
                            otherwise, all the words up  to  and  including  a
                            word  matching  the  pattern  are  to be completed
                            using the action.

                            Multiple colons are treated  as  for  the  `*:...'
                            forms for ordinary arguments:  when the message is
                            preceded by two colons, the  words  special  array
                            and  the  CURRENT  special  parameter are modified
                            during the execution or evaluation of  the  action
                            to refer only to the words after the option.  When
                            preceded by three colons,  they  are  modified  to
                            refer  only  to the words covered by this descrip-
                            tion.

              Any literal colon in an optname, message, or action must be pre-
              ceded by a backslash, `\:'.

              Each of the forms above may be preceded by a list in parentheses
              of option names and argument numbers.  If the given option is on
              the  command line, the options and arguments indicated in paren-
              theses  will  not  be  offered.   For  example,  `(-two   -three
              1)-one:...'  completes the option `-one'; if this appears on the
              command line, the options -two and -three and the first ordinary
              argument will not be completed after it.  `(-foo):...' specifies
              an ordinary argument completion; -foo will not be  completed  if
              that argument is already present.

              Other  items may appear in the list of excluded options to indi-
              cate various other items that should not  be  applied  when  the
              current specification is matched: a single star (*) for the rest
              arguments (i.e. a specification of the form  `*:...');  a  colon
              (:) for all normal (non-option-) arguments; and a hyphen (-) for
              all options.  For example, if `(*)' appears before an option and
              the  option  appears  on the command line, the list of remaining
              arguments (those shown in the above table beginning  with  `*:')
              will not be completed.

              To aid in reuse of specifications, it is possible to precede any
              of the forms above with `!'; then the form  will  no  longer  be
              completed,  although  if  the  option or argument appears on the
              command line they will be skipped as normal.  The main  use  for
              this is when the arguments are given by an array, and _arguments
              is called repeatedly for more specific contexts:  on  the  first
              call  `_arguments  $global_options'  is  used, and on subsequent
              calls `_arguments !$^global_options'.

              specs: actions

              In each of the forms above the action determines how completions
              should  be generated.  Except for the `->string' form below, the
              action will be executed by calling the _all_labels  function  to
              process  all  tag labels.  No special handling of tags is needed
              unless a function call introduces a new one.

              The functions called to execute actions will be called with  the
              elements  of  the  array  named by the `-O name' option as argu-
              ments.  This can be used, for example, to pass the same  set  of
              options for the compadd builtin to all actions.

              The forms for action are as follows.

               (single unquoted space)
                     This  is  useful  where an argument is required but it is
                     not possible or desirable to  generate  matches  for  it.
                     The  message will be displayed but no completions listed.
                     Note that even in this case the colon at the end  of  the
                     message  is needed; it may only be omitted when neither a
                     message nor an action is given.

              (item1 item2 ...)
                     One of a list of possible matches, for example:

                            :foo:(foo bar baz)

              ((item1\:desc1 ...))
                     Similar to the above, but with descriptions for each pos-
                     sible  match.   Note the backslash before the colon.  For
                     example,

                            :foo:((a\:bar b\:baz))

                     The matches will be listed together with  their  descrip-
                     tions if the description style is set with the values tag
                     in the context.

              ->string
                     In this form,  _arguments  processes  the  arguments  and
                     options  and then returns control to the calling function
                     with parameters set to indicate the state of  processing;
                     the  calling function then makes its own arrangements for
                     generating  completions.   For  example,  functions  that
                     implement a state machine can use this type of action.

                     Where _arguments encounters action in the `->string' for-
                     mat, it will strip all leading  and  trailing  whitespace
                     from  string  and  set  the array state to the set of all
                     strings for which an action is to be performed.  The ele-
                     ments  of  the  array state_descr are assigned the corre-
                     sponding message field from each optarg  containing  such
                     an action.

                     By default and in common with all other well behaved com-
                     pletion functions, _arguments returns status zero  if  it
                     was  able to add matches and non-zero otherwise. However,
                     if the -R option is given, _arguments will instead return
                     a status of 300 to indicate that $state is to be handled.

                     In  addition  to $state and $state_descr, _arguments also
                     sets  the  global  parameters   `context',   `line'   and
                     `opt_args'  as  described  below,  and does not reset any
                     changes made to the special parameters such as PREFIX and
                     words.   This  gives  the  calling function the choice of
                     resetting these  parameters  or  propagating  changes  in
                     them.

                     A  function  calling  _arguments with at least one action
                     containing a `->string' must therefore declare  appropri-
                     ate local parameters:

                            local context state state_descr line
                            typeset -A opt_args

                     to  prevent  _arguments from altering the global environ-
                     ment.

              {eval-string}
                     A string in braces is evaluated as shell code to generate
                     matches.   If  the eval-string itself does not begin with
                     an opening parenthesis or brace it is split into separate
                     words before execution.

              = action
                     If  the  action starts with `= ' (an equals sign followed
                     by a space), _arguments will insert the contents  of  the
                     argument  field  of  the current context as the new first
                     element in the words  special  array  and  increment  the
                     value  of  the  CURRENT  special parameter.  This has the
                     effect of inserting a dummy word onto the completion com-
                     mand  line  while not changing the point at which comple-
                     tion is taking place.

                     This is most useful  with  one  of  the  specifiers  that
                     restrict  the  words  on  the  command  line on which the
                     action is to operate  (the  two-  and  three-colon  forms
                     above).   One  particular  use  is  when an action itself
                     causes _arguments on a restricted range; it is  necessary
                     to  use  this trick to insert an appropriate command name
                     into the range for the second call to  _arguments  to  be
                     able to parse the line.

               word...
              word...
                     This  covers  all  forms  other than those above.  If the
                     action starts with a space, the remaining list  of  words
                     will be invoked unchanged.

                     Otherwise  it  will  be  invoked  with some extra strings
                     placed after the first word; these are to be passed  down
                     as  options to the compadd builtin.  They ensure that the
                     state specified by _arguments, in particular the descrip-
                     tions  of  options  and arguments, is correctly passed to
                     the completion command.  These additional  arguments  are
                     taken  from  the array parameter `expl'; this will be set
                     up before executing the action and hence may be  referred
                     to  inside  it,  typically  in  an  expansion of the form
                     `$expl[@]' which preserves empty elements of the array.

              During the performance of the action the array  `line'  will  be
              set  to  the  normal  arguments  from the command line, i.e. the
              words from the command line after the command name excluding all
              options and their arguments.  Options are stored in the associa-
              tive array `opt_args' with option names as keys and their  argu-
              ments  as the values.  For options that have more than one argu-
              ment these are given as one string, separated  by  colons.   All
              colons  and  backslashes  in the original arguments are preceded
              with backslashes.

              The parameter `context' is set when  returning  to  the  calling
              function to perform an action of the form `->string'.  It is set
              to an array of elements corresponding to the elements of $state.
              Each  element  is  a suitable name for the argument field of the
              context: either a string of the form `option-opt-n' for the n'th
              argument  of  the  option  -opt,  or a string of the form `argu-
              ment-n' for the n'th argument.  For `rest'  arguments,  that  is
              those  in  the list at the end not handled by position, n is the
              string `rest'.  For example, when completing the argument of the
              -o option, the name is `option-o-1', while for the second normal
              (non-option-) argument it is `argument-2'.

              Furthermore, during the evaluation of  the  action  the  context
              name  in  the curcontext parameter is altered to append the same
              string that is stored in the context parameter.

              The option -C tells _arguments to modify the curcontext  parame-
              ter  for  an action of the form `->state'.  This is the standard
              parameter used to keep track of the current  context.   Here  it
              (and  not the context array) should be made local to the calling
              function to avoid passing back the modified value and should  be
              initialised to the current value at the start of the function:

                     local curcontext="$curcontext"

              This  is  useful where it is not possible for multiple states to
              be valid together.

              Specifying multiple sets of options

              It is possible to specify multiple sets of options and arguments
              with  the  sets separated by single hyphens.  The specifications
              before the first hyphen (if any) are shared by all the remaining
              sets.  The first word in every other set provides a name for the
              set which may  appear  in  exclusion  lists  in  specifications,
              either  alone  or  before  one  of the possible values described
              above.  In the second case a `-' should appear between this name
              and the remainder.

              For example:

                     _arguments \
                         -a \
                       - set1 \
                         -c \
                       - set2 \
                         -d \
                         ':arg:(x2 y2)'

              This  defines  two  sets.   When  the  command line contains the
              option `-c', the `-d' option and the argument will not  be  con-
              sidered possible completions.  When it contains `-d' or an argu-
              ment, the option `-c' will not be  considered.   However,  after
              `-a' both sets will still be considered valid.

              If  an option in a set appears on the command line, it is stored
              in the associative array `opt_args' with 'set-option' as a  key.
              In the example above, a key `set1--c' is used if the option `-c'
              is on the command line.

              If the name given for one of the mutually exclusive sets  is  of
              the form `(name)' then only one value from each set will ever be
              completed; more formally, all specifications are mutually exclu-
              sive  to all other specifications in the same set.  This is use-
              ful for defining multiple sets of  options  which  are  mutually
              exclusive  and  in which the options are aliases for each other.
              For example:

                     _arguments \
                         -a -b \
                       - '(compress)' \
                         {-c,--compress}'[compress]' \
                       - '(uncompress)' \
                         {-d,--decompress}'[decompress]'

              As the completion code has to parse the command line  separately
              for  each  set  this form of argument is slow and should only be
              used when necessary.  A useful alternative is  often  an  option
              specification with rest-arguments (as in `-foo:*:...'); here the
              option -foo swallows up all remaining arguments as described  by
              the optarg definitions.

              Deriving spec forms from the help output

              The  option `--' allows _arguments to work out the names of long
              options that support the `--help' option which  is  standard  in
              many GNU commands.  The command word is called with the argument
              `--help' and the output examined for option names.  Clearly,  it
              can  be dangerous to pass this to commands which may not support
              this option as the behaviour of the command is unspecified.

              In addition to options, `_arguments --' will try to  deduce  the
              types   of   arguments  available  for  options  when  the  form
              `--opt=val' is valid.  It is also possible to provide  hints  by
              examining  the  help  text of the command and adding helpspec of
              the form `pattern:message:action'; note  that  other  _arguments
              spec  forms  are  not  used.  The pattern is matched against the
              help text for an option, and  if  it  matches  the  message  and
              action  are  used as for other argument specifiers.  The special
              case of `*:' means both message and action are empty, which  has
              the  effect of causing options having no description in the help
              output to be ordered in listings ahead of options  that  have  a
              description.

              For example:

                     _arguments -- '*\*:toggle:(yes no)' \
                                   '*=FILE*:file:_files' \
                                   '*=DIR*:directory:_files -/' \
                                   '*=PATH*:directory:_files -/'

              Here,  `yes'  and  `no'  will  be  completed  as the argument of
              options whose description ends in a star;  file  names  will  be
              completed  for options that contain the substring `=FILE' in the
              description; and directories will be completed for options whose
              description  contains  `=DIR' or `=PATH'.  The last three are in
              fact the default and so need not be given  explicitly,  although
              it is possible to override the use of these patterns.  A typical
              help text which uses this feature is:

                       -C, --directory=DIR          change to directory DIR

              so that the above specifications will cause  directories  to  be
              completed after `--directory', though not after `-C'.

              Note also that _arguments tries to find out automatically if the
              argument for an option  is  optional.   This  can  be  specified
              explicitly by doubling the colon before the message.

              If the pattern ends in `(-)', this will be removed from the pat-
              tern and the action will be used only directly  after  the  `=',
              not  in the next word.  This is the behaviour of a normal speci-
              fication defined with the form `=-'.

              The `_arguments --' can be followed by the option `-i  patterns'
              to give patterns for options which are not to be completed.  The
              patterns can be given as the name of an array parameter or as  a
              literal list in parentheses.  For example,

                     _arguments -- -i \
                         "(--(en|dis)able-FEATURE*)"

              will  cause  completion to ignore the options `--enable-FEATURE'
              and `--disable-FEATURE' (this example is useful with GNU config-
              ure).

              The  `_arguments --' form can also be followed by the option `-s
              pair' to describe option aliases.  The pair consists of  a  list
              of alternating patterns and corresponding replacements, enclosed
              in parens and quoted so that it forms a single argument word  in
              the _arguments call.

              For example, some configure-script help output describes options
              only as `--enable-foo', but the script also accepts the  negated
              form `--disable-foo'.  To allow completion of the second form:

                     _arguments -- -s "((#s)--enable- --disable-)"

              Miscellaneous notes

              Finally,  note  that _arguments generally expects to be the pri-
              mary function handling any completion for which it is used.   It
              may  have side effects which change the treatment of any matches
              added by other functions called after it.  To combine _arguments
              with  other  functions,  those functions should be called either
              before _arguments, as an action within a spec,  or  in  handlers
              for `->state' actions.

              Here is a more general example of the use of _arguments:

                     _arguments '-l+:left border:' \
                                '-format:paper size:(letter A4)' \
                                '*-copy:output file:_files::resolution:(300 600)' \
                                ':postscript file:_files -g \*.\(ps\|eps\)' \
                                '*:page number:'

              This describes three options: `-l', `-format', and `-copy'.  The
              first takes one argument described as `left border' for which no
              completion  will  be  offered  because of the empty action.  Its
              argument may come directly after the `-l' or it may be given  as
              the next word on the line.

              The  `-format'  option  takes  one  argument  in  the next word,
              described as `paper size' for which only  the  strings  `letter'
              and `A4' will be completed.

              The `-copy' option may appear more than once on the command line
              and takes two arguments.  The first is  mandatory  and  will  be
              completed as a filename.  The second is optional (because of the
              second colon before the description `resolution')  and  will  be
              completed from the strings `300' and `600'.

              The  last two descriptions say what should be completed as argu-
              ments.  The first describes the first argument as a  `postscript
              file' and makes files ending in `ps' or `eps' be completed.  The
              last description gives all other arguments the description `page
              numbers' but does not offer completions.

       _cache_invalid cache_identifier
              This  function returns status zero if the completions cache cor-
              responding to the given cache identifier needs  rebuilding.   It
              determines  this  by  looking  up the cache-policy style for the
              current context.  This should provide a function name  which  is
              run  with  the  full path to the relevant cache file as the only
              argument.

              Example:

                     _example_caching_policy () {
                         # rebuild if cache is more than a week old
                         local -a oldp
                         oldp=( "$1"(Nm+7) )
                         (( $#oldp ))
                     }

       _call_function return name [ arg ... ]
              If a function name exists, it is called with the arguments args.
              The  return  argument gives the name of a parameter in which the
              return status from the function name should be stored; if return
              is empty or a single hyphen it is ignored.

              The  return status of _call_function itself is zero if the func-
              tion name exists and was called and non-zero otherwise.

       _call_program [ -p ] tag string ...
              This function provides a mechanism for the user to override  the
              use  of an external command.  It looks up the command style with
              the supplied tag.  If the style is set, its value is used as the
              command to execute.  The strings from the call to _call_program,
              or from the style if set, are concatenated with  spaces  between
              them  and  the resulting string is evaluated.  The return status
              is the return status of the command called.

              If the option `-p' is supplied it  indicates  that  the  command
              output  is  influenced by the permissions it is run with. If the
              gain-privileges style is set to true,  _call_program  will  make
              use of commands such as sudo, if present on the command-line, to
              match the permissions to whatever the final command is likely to
              run  under.  When  looking  up  the  gain-privileges and command
              styles, the command component of the  zstyle  context  will  end
              with a slash (`/') followed by the command that would be used to
              gain privileges.

       _combination [ -s pattern ] tag style spec ... field opts ...
              This function is used to complete combinations of  values,   for
              example  pairs  of  hostnames and usernames.  The style argument
              gives the style which defines the pairs; it is looked  up  in  a
              context with the tag specified.

              The style name consists of field names separated by hyphens, for
              example `users-hosts-ports'.  For each  field  for  a  value  is
              already known, a spec of the form `field=pattern' is given.  For
              example, if the command line so far specifies a user `pws',  the
              argument `users=pws' should appear.

              The  next  argument  with no equals sign is taken as the name of
              the field for which completions should be generated  (presumably
              not one of the fields for which the value is known).

              The matches generated will be taken from the value of the style.
              These should contain the possible values for the combinations in
              the  appropriate  order  (users,  hosts,  ports  in  the example
              above).  The different  fields  the  values  for  the  different
              fields  are  separated  by colons.  This can be altered with the
              option -s to _combination which specifies a pattern.   Typically
              this  is  a  character  class, as for example `-s "[:@]"' in the
              case of the users-hosts style.    Each `field=pattern'  specifi-
              cation  restricts the completions which apply to elements of the
              style with appropriately matching fields.

              If no style with the given name is defined for the given tag, or
              if  none  of  the strings in style's value match, but a function
              name of the required field preceded by an underscore is defined,
              that function will be called to generate the matches.  For exam-
              ple, if there is no `users-hosts-ports' or no matching  hostname
              when  a  host  is required, the function `_hosts' will automati-
              cally be called.

              If the same name is used for more than one field,  in  both  the
              `field=pattern'  and  the  argument  that  gives the name of the
              field to be completed, the number of the  field  (starting  with
              one)  may  be  given after the fieldname, separated from it by a
              colon.

              All arguments after the required field name are passed  to  com-
              padd  when  generating  matches  from the style value, or to the
              functions for the fields if they are called.

       _command_names [ -e | - ]
              This function completes words that are valid  at  command  posi-
              tion:  names  of  aliases, builtins, hashed commands, functions,
              and so on.  With the -e flag,  only  hashed  commands  are  com-
              pleted.  The - flag is ignored.

       _completers [ -p ]
              This function completes names of completers.

              -p     Include the leading underscore (`_') in the matches.


       _describe [-12JVx] [ -oO | -t tag ] descr name1 [ name2 ] [ opt ... ]
                 [ -- name1 [ name2 ] [ opt ... ] ... ]
              This  function associates completions with descriptions.  Multi-
              ple groups separated by -- can  be  supplied,  potentially  with
              different completion options opts.

              The  descr  is taken as a string to display above the matches if
              the format style for the descriptions tag is set.  This is  fol-
              lowed  by one or two names of arrays followed by options to pass
              to compadd.  The array name1 contains the  possible  completions
              with  their  descriptions  in the form `completion:description'.
              Any literal colons in completion must be  quoted  with  a  back-
              slash.   If  a name2 is given, it should have the same number of
              elements as name1; in this case the corresponding  elements  are
              added  as possible completions instead of the completion strings
              from name1.  The completion list will  retain  the  descriptions
              from name1.  Finally, a set of completion options can appear.

              If  the  option  `-o'  appears  before  the  first argument, the
              matches added will be treated as names of command options  (N.B.
              not  shell  options),  typically following a `-', `--' or `+' on
              the command line.  In this case _describe uses  the  prefix-hid-
              den, prefix-needed and verbose styles to find out if the strings
              should be added as completions and if the descriptions should be
              shown.   Without the `-o' option, only the verbose style is used
              to decide how descriptions are shown.  If `-O' is  used  instead
              of  `-o',  command  options are completed as above but _describe
              will not handle the prefix-needed style.

              With the -t option a tag can be specified.  The default is `val-
              ues' or, if the -o option is given, `options'.

              The options -1, -2, -J, -V, -x are passed to _next_label.

              If  selected  by  the  list-grouped style, strings with the same
              description will appear together in the list.

              _describe uses the _all_labels function to generate the matches,
              so it does not need to appear inside a loop over tag labels.

       _description [ -x ] [ -12VJ ] tag name descr [ spec ... ]
              This function is not to be confused with the previous one; it is
              used as a helper function for creating options to  compadd.   It
              is  buried  inside many of the higher level completion functions
              and so often does not need to be called directly.

              The styles listed below are tested in the current context  using
              the  given  tag.  The resulting options for compadd are put into
              the array named name (this is  traditionally  `expl',  but  this
              convention  is  not  enforced).   The description for the corre-
              sponding set of matches is passed to the function in descr.

              The styles tested are: format, hidden, matcher, ignored-patterns
              and  group-name.  The format style is first tested for the given
              tag and then for the descriptions tag if  no  value  was  found,
              while  the  remainder  are  only tested for the tag given as the
              first argument.  The function also calls _setup which tests some
              more styles.

              The  string  returned by the format style (if any) will be modi-
              fied so that the sequence `%d' is replaced by the descr given as
              the  third argument without any leading or trailing white space.
              If, after removing the white  space,  the  descr  is  the  empty
              string,  the  format  style will not be used and the options put
              into the name array will not contain an explanation string to be
              displayed above the matches.

              If  _description  is  called with more than three arguments, the
              additional specs should be of the form `char:str'.  These supply
              escape sequence replacements for the format style: every appear-
              ance of `%char' will be replaced by string.

              If the -x option is given, the description  will  be  passed  to
              compadd  using  the  -x  option instead of the default -X.  This
              means that the description will be displayed even if  there  are
              no corresponding matches.

              The  options  placed  in  the  array  name  take  account of the
              group-name style, so matches are  placed  in  a  separate  group
              where necessary.  The group normally has its elements sorted (by
              passing the option -J to compadd), but  if  an  option  starting
              with  `-V',  `-J', `-1', or `-2' is passed to _description, that
              option will be included in the array.  Hence it is possible  for
              the  completion  group to be unsorted by giving the option `-V',
              `-1V', or `-2V'.

              In most cases, the function will be used like this:

                     local expl
                     _description files expl file
                     compadd "$expl[@]" - "$files[@]"

              Note the use of the parameter expl, the hyphen, and the list  of
              matches.  Almost all calls to compadd within the completion sys-
              tem use a  similar  format;  this  ensures  that  user-specified
              styles are correctly passed down to the builtins which implement
              the internals of completion.

       _dir_list [ -s sep ] [ -S ]
              Complete a list of directory names separated by colons (the same
              format as $PATH).

              -s sep Use  sep  as  separator between items.  sep defaults to a
                     colon (`:').

              -S     Add sep instead of slash (`/') as an autoremoveable  suf-
                     fix.

       _dispatch context string ...
              This  sets  the current context to context and looks for comple-
              tion functions to handle this context  by  hunting  through  the
              list  of  command  names or special contexts (as described above
              for compdef) given as strings.  The first completion function to
              be defined for one of the contexts in the list is used to gener-
              ate matches.  Typically, the last string is -default-  to  cause
              the function for default completion to be used as a fallback.

              The  function  sets  the  parameter $service to the string being
              tried, and sets the context/command field (the  fourth)  of  the
              $curcontext  parameter  to  the context given as the first argu-
              ment.

       _email_addresses [ -c ] [ -n plugin ]
              Complete email addresses.  Addresses are provided by plugins.

              -c     Complete bare localhost@domain.tld addresses,  without  a
                     name  part  or  a  comment.   Without this option, RFC822
                     `Firstname Lastname <address>' strings are completed.

              -n plugin
                     Complete aliases from plugin.

              The following plugins are available by default: _email-ldap (see
              the  filter  style),  _email-local (completes user@hostname Unix
              addresses),  _email-mail  (completes  aliases  from  ~/.mailrc),
              _email-mush, _email-mutt, and _email-pine.

              Addresses  from  the  _email-foo  plugin are added under the tag
              `email-foo'.

              Writing plugins

              Plugins are written as separate functions  with  names  starting
              with `_email-'.  They are invoked with the -c option and compadd
              options.  They should either do their own completion or set  the
              $reply  array  to  a list of `alias:address' elements and return
              300.  New plugins will be picked up and run automatically.

       _files The function _files calls _path_files with all the arguments  it
              was  passed  except for -g and -/.  The use of these two options
              depends on the setting of the  file-patterns style.

              This function  accepts  the  full  set  of  options  allowed  by
              _path_files, described below.

       _gnu_generic
              This function is a simple wrapper around the _arguments function
              described above.  It can be used to determine automatically  the
              long  options  understood  by  commands that produce a list when
              passed the option `--help'.  It is intended  to  be  used  as  a
              top-level completion function in its own right.  For example, to
              enable option completion for the commands foo and bar, use

                     compdef _gnu_generic foo bar

              after the call to compinit.

              The completion system as supplied is conservative in its use  of
              this  function,  since  it  is  important to be sure the command
              understands the option `--help'.

       _guard [ options ] pattern descr
              This function displays descr if pattern matches the string to be
              completed.   It  is  intended  to  be used in the action for the
              specifications passed to _arguments and similar functions.

              The return status is zero if the message was displayed  and  the
              word to complete is not empty, and non-zero otherwise.

              The  pattern may be preceded by any of the options understood by
              compadd that are passed down from _description, namely  -M,  -J,
              -V,  -1,  -2,  -n,  -F  and  -X.   All  of these options will be
              ignored.  This fits in conveniently  with  the  argument-passing
              conventions of actions for _arguments.

              As  an  example,  consider  a  command taking the options -n and
              -none, where -n must be followed by a numeric value in the  same
              word.  By using:

                     _arguments '-n-: :_guard "[0-9]#" "numeric value"' '-none'

              _arguments  can  be  made  to  both display the message `numeric
              value' and complete options after `-n<TAB>'.   If  the  `-n'  is
              already  followed  by  one or more digits (the pattern passed to
              _guard) only the message will be displayed; if the `-n' is  fol-
              lowed by another character, only options are completed.

       _message [ -r12 ] [ -VJ group ] descr
       _message -e [ tag ] descr
              The  descr  is used in the same way as the third argument to the
              _description function, except that  the  resulting  string  will
              always  be shown whether or not matches were generated.  This is
              useful for displaying a help message in places where no  comple-
              tions can be generated.

              The  format  style  is  examined with the messages tag to find a
              message; the usual tag, descriptions, is used only if the  style
              is not set with the former.

              If  the -r option is given, no style is used; the descr is taken
              literally as the string to display.  This is  most  useful  when
              the descr comes from a pre-processed argument list which already
              contains an expanded description.

              The -12VJ options and the group are passed to compadd and  hence
              determine the group the message string is added to.

              The  second -e form gives a description for completions with the
              tag tag to be shown even if there are no matches for  that  tag.
              This  form is called by _arguments in the event that there is no
              action for an option specification.  The tag can be omitted  and
              if so the tag is taken from the parameter $curtag; this is main-
              tained by the completion system and so is usually correct.  Note
              that  if  there  are  no  matches  at  the time this function is
              called, compstate[insert] is cleared, so additional matches gen-
              erated later are not inserted on the command line.

       _multi_parts [ -i ] sep array
              The  argument  sep  is  a separator character.  The array may be
              either the name of an array parameter or a literal array in  the
              form  `(foo  bar)',  a  parenthesised list of words separated by
              whitespace.  The possible completions are the strings  from  the
              array.   However,  each chunk delimited by sep will be completed
              separately.  For example, the _tar function uses `_multi_parts /
              patharray'  to  complete partial file paths from the given array
              of complete file paths.

              The -i option causes _multi_parts to insert a unique match  even
              if  that  requires  multiple separators to be inserted.  This is
              not usually the expected behaviour with filenames,  but  certain
              other types of completion, for example those with a fixed set of
              possibilities, may be more suited to this form.

              Like other utility functions, this function  accepts  the  `-V',
              `-J',  `-1',  `-2',  `-n',  `-f',  `-X', `-M', `-P', `-S', `-r',
              `-R', and `-q' options and passes them to the compadd builtin.

       _next_label [ -x ] [ -12VJ ] tag name descr [ option ... ]
              This function is used to implement the loop over  different  tag
              labels for a particular tag as described above for the tag-order
              style.  On each call it checks to see if there are any more  tag
              labels;  if there is it returns status zero, otherwise non-zero.
              As this function requires a current  tag  to  be  set,  it  must
              always follow a call to _tags or _requested.

              The  -x12VJ  options and the first three arguments are passed to
              the _description function.  Where appropriate the  tag  will  be
              replaced  by a tag label in this call.  Any description given in
              the  tag-order  style  is  preferred  to  the  descr  passed  to
              _next_label.

              The options given after the descr are set in the parameter given
              by name, and hence are to be passed to compadd or whatever func-
              tion is called to add the matches.

              Here  is  a  typical  use of this function for the tag foo.  The
              call to _requested determines if tag foo is required at all; the
              loop  over _next_label handles any labels defined for the tag in
              the tag-order style.

                     local expl ret=1
                     ...
                     if _requested foo; then
                       ...
                       while _next_label foo expl '...'; do
                         compadd "$expl[@]" ... && ret=0
                       done
                       ...
                     fi
                     return ret

       _normal
              This is the standard function called to handle  completion  out-
              side  any  special -context-.  It is called both to complete the
              command word and also the arguments for a command.  In the  sec-
              ond  case,  _normal looks for a special completion for that com-
              mand, and if there is  none  it  uses  the  completion  for  the
              -default- context.

              A  second  use is to reexamine the command line specified by the
              $words array and the $CURRENT parameter after  those  have  been
              modified.   For  example,  the  function _precommand, which com-
              pletes after pre-command specifiers such as nohup,  removes  the
              first  word from the words array, decrements the CURRENT parame-
              ter, then calls _normal again.  The effect is  that  `nohup  cmd
              ...' is treated in the same way as `cmd ...'.

              If  the command name matches one of the patterns given by one of
              the options -p or -P to compdef,  the  corresponding  completion
              function  is called and then the parameter _compskip is checked.
              If it is set completion is terminated at that point even  if  no
              matches  have  been  found.   This  is the same effect as in the
              -first- context.

       _options
              This can be used to complete the names  of  shell  options.   It
              provides  a  matcher  specification that ignores a leading `no',
              ignores underscores and allows upper-case letters to match their
              lower-case   counterparts   (for   example,   `glob',  `noglob',
              `NO_GLOB' are all completed).  Any arguments are  propagated  to
              the compadd builtin.

       _options_set and _options_unset
              These  functions  complete  only  set or unset options, with the
              same matching specification used in the _options function.

              Note that you need to uncomment a few lines  in  the  _main_com-
              plete  function for these functions to work properly.  The lines
              in question are used to store  the  option  settings  in  effect
              before  the completion widget locally sets the options it needs.
              Hence these functions are not generally used by  the  completion
              system.

       _parameters
              This is used to complete the names of shell parameters.

              The  option  `-g  pattern'  limits  the completion to parameters
              whose type matches the pattern.  The type of a parameter is that
              shown by `print ${(t)param}', hence judicious use of `*' in pat-
              tern is probably necessary.

              All other arguments are passed to the compadd builtin.

       _path_files
              This function is used throughout the completion system  to  com-
              plete  filenames.   It  allows completion of partial paths.  For
              example,  the  string   `/u/i/s/sig'   may   be   completed   to
              `/usr/include/sys/signal.h'.

              The options accepted by both _path_files and _files are:

              -f     Complete all filenames.  This is the default.

              -/     Specifies that only directories should be completed.

              -g pattern
                     Specifies  that only files matching the pattern should be
                     completed.

              -W paths
                     Specifies path prefixes that are to be prepended  to  the
                     string  from  the  command line to generate the filenames
                     but that should not be inserted as completions nor  shown
                     in  completion  listings.  Here, paths may be the name of
                     an array parameter, a literal list of paths  enclosed  in
                     parentheses or an absolute pathname.

              -F ignored-files
                     This  behaves as for the corresponding option to the com-
                     padd builtin.  It gives direct control over  which  file-
                     names  should  be ignored.  If the option is not present,
                     the ignored-patterns style is used.

              Both _path_files and _files also accept  the  following  options
              which are passed to compadd: `-J', `-V', `-1', `-2', `-n', `-X',
              `-M', `-P', `-S', `-q', `-r', and `-R'.

              Finally, the  _path_files  function   uses  the  styles  expand,
              ambiguous,  special-dirs,  list-suffixes and file-sort described
              above.


       _pick_variant [ -b builtin-label ] [ -c command ] [ -r name ]
                     label=pattern ... label [ arg ... ]
              This function is used to resolve situations where a single  com-
              mand  name  requires  more  than  one  type  of handling, either
              because it has more than one variant or because there is a  name
              clash between two different commands.

              The  command to run is taken from the first element of the array
              words unless this is overridden by the option -c.  This  command
              is  run  and  its  output is compared with a series of patterns.
              Arguments to be passed to the command can be  specified  at  the
              end after all the other arguments.  The patterns to try in order
              are given by the arguments label=pattern; if the output of `com-
              mand  arg  ...'  contains pattern, then label is selected as the
              label for the command variant.  If none of the  patterns  match,
              the final command label is selected and status 1 is returned.

              If the `-b builtin-label' is given, the command is tested to see
              if it is provided as a shell builtin,  possibly  autoloaded;  if
              so,  the  label  builtin-label  is selected as the label for the
              variant.

              If the `-r name' is given, the label picked  is  stored  in  the
              parameter named name.

              The  results  are  also  cached  in the _cmd_variant associative
              array indexed by the name of the command run.

       _regex_arguments name spec ...
              This function generates a completion function name which matches
              the  specifications  specs,  a  set  of  regular  expressions as
              described below.  After running _regex_arguments,  the  function
              name should be called as a normal completion function.  The pat-
              tern to be matched is given by the contents of the  words  array
              up  to  the  current  cursor  position joined together with null
              characters; no quotation is applied.

              The arguments are grouped as sets of alternatives  separated  by
              `|',  which  are  tried  one  after the other until one matches.
              Each alternative consists of a one or more specifications  which
              are  tried  left  to  right,  with  each  pattern  matched being
              stripped in turn from the command line being tested,  until  all
              of  the  group  succeeds or until one fails; in the latter case,
              the next alternative is tried.  This structure can  be  repeated
              to  arbitrary depth by using parentheses; matching proceeds from
              inside to outside.

              A special procedure is applied  if  no  test  succeeds  but  the
              remaining command line string contains no null character (imply-
              ing the remaining word is the one for which completions  are  to
              be  generated).   The  completion  target  is  restricted to the
              remaining word and any actions for  the  corresponding  patterns
              are  executed.   In this case, nothing is stripped from the com-
              mand line string.  The order of evaluation of the actions can be
              determined by the tag-order style; the various formats supported
              by _alternative can be used in action.  The descr  is  used  for
              setting up the array parameter expl.

              Specification  arguments  take  one of following forms, in which
              metacharacters such as `(', `)', `#' and `|' should be quoted.

              /pattern/ [%lookahead%] [-guard] [:tag:descr:action]
                     This is a single primitive component.  The function tests
                     whether  the  combined  pattern  `(#b)((#B)pattern)looka-
                     head*' matches the command line string.  If  so,  `guard'
                     is  evaluated and its return status is examined to deter-
                     mine if the test has succeeded.  The pattern string  `[]'
                     is  guaranteed  never  to  match.   The  lookahead is not
                     stripped from the command line before the next pattern is
                     examined.

                     The  argument  starting with : is used in the same manner
                     as an argument to _alternative.

                     A component is used as follows: pattern is tested to  see
                     if  the component already exists on the command line.  If
                     it does, any following  specifications  are  examined  to
                     find  something  to  complete.  If a component is reached
                     but no such pattern exists yet on the command  line,  the
                     string  containing the action is used to generate matches
                     to insert at that point.

              /pattern/+ [%lookahead%] [-guard] [:tag:descr:action]
                     This is similar to `/pattern/ ...' but the left  part  of
                     the command line string (i.e. the part already matched by
                     previous patterns) is also considered part of the comple-
                     tion target.

              /pattern/- [%lookahead%] [-guard] [:tag:descr:action]
                     This is similar to `/pattern/ ...' but the actions of the
                     current and previously matched patterns are ignored  even
                     if the following `pattern' matches the empty string.

              ( spec )
                     Parentheses may be used to groups specs; note each paren-
                     thesis is a single argument to _regex_arguments.

              spec # This allows any number of repetitions of spec.

              spec spec
                     The two specs are to be matched one after  the  other  as
                     described above.

              spec | spec
                     Either of the two specs can be matched.

              The  function  _regex_words  can be used as a helper function to
              generate matches for a set of alternative  words  possibly  with
              their own arguments as a command line argument.

              Examples:

                     _regex_arguments _tst /$'[^\0]#\0'/ \
                         /$'[^\0]#\0'/ :'compadd aaa'

              This  generates  a  function _tst that completes aaa as its only
              argument.  The tag and description  for  the  action  have  been
              omitted for brevity (this works but is not recommended in normal
              use).  The first component matches the command  word,  which  is
              arbitrary; the second matches  any argument.  As the argument is
              also arbitrary, any following component would not depend on  aaa
              being present.

                     _regex_arguments _tst /$'[^\0]#\0'/ \
                         /$'aaa\0'/ :'compadd aaa'

              This  is  a  more  typical use; it is similar, but any following
              patterns would only match if aaa was present as the first  argu-
              ment.

                     _regex_arguments _tst /$'[^\0]#\0'/ \( \
                         /$'aaa\0'/ :'compadd aaa' \
                         /$'bbb\0'/ :'compadd bbb' \) \#

              In  this  example, an indefinite number of command arguments may
              be completed.  Odd arguments are completed as aaa and even argu-
              ments  as  bbb.   Completion fails unless the set of aaa and bbb
              arguments before the current one is matched correctly.

                     _regex_arguments _tst /$'[^\0]#\0'/ \
                         \( /$'aaa\0'/ :'compadd aaa' \| \
                         /$'bbb\0'/ :'compadd bbb' \) \#

              This is similar, but either aaa or bbb may be completed for  any
              argument.  In this case _regex_words could be used to generate a
              suitable expression for the arguments.

       _regex_words tag description spec ...
              This  function  can  be  used  to  generate  arguments  for  the
              _regex_arguments  command  which  may  be  inserted at any point
              where a set of rules is expected.  The tag and description  give
              a  standard  tag  and description pertaining to the current con-
              text.  Each spec contains two or three arguments separated by  a
              colon: note that there is no leading colon in this case.

              Each  spec  gives one of a set of words that may be completed at
              this point, together with arguments.  It is thus roughly equiva-
              lent  to the _arguments function when used in normal (non-regex)
              completion.

              The part of the spec before the first colon is the  word  to  be
              completed.   This  may  contain a *; the entire word, before and
              after the * is completed, but only the  text  before  the  *  is
              required  for  the  context to be matched, so that further argu-
              ments may be completed after the abbreviated form.

              The second part of spec is a description for the word being com-
              pleted.

              The  optional third part of the spec describes how words follow-
              ing the one being completed are themselves to be completed.   It
              will be evaluated in order to avoid problems with quoting.  This
              means that typically it contains a reference to  an  array  con-
              taining previously generated regex arguments.

              The  option  -t term specifies a terminator for the word instead
              of the usual space.  This is handled as an auto-removable suffix
              in the manner of the option -s sep to _values.

              The  result  of  the processing by _regex_words is placed in the
              array reply, which should be made local to the calling function.
              If the set of words and arguments may be matched repeatedly, a #
              should be appended to the generated array at that point.

              For example:

                     local -a reply
                     _regex_words mydb-commands 'mydb commands' \
                       'add:add an entry to mydb:$mydb_add_cmds' \
                       'show:show entries in mydb'
                     _regex_arguments _mydb "$reply[@]"
                     _mydb "$@"

              This shows a completion function for a command mydb which  takes
              two  command  arguments, add and show.  show takes no arguments,
              while the arguments for add have already  been  prepared  in  an
              array  mydb_add_cmds,  quite  possibly  by  a  previous  call to
              _regex_words.

       _requested [ -x ] [ -12VJ ] tag [ name descr [ command [ arg ... ] ]
              This function is called to decide whether a tag  already  regis-
              tered  by  a call to _tags (see below) has been requested by the
              user and hence  completion  should  be  performed  for  it.   It
              returns  status zero if the tag is requested and non-zero other-
              wise.  The function is typically used as part  of  a  loop  over
              different tags as follows:

                     _tags foo bar baz
                     while _tags; do
                       if _requested foo; then
                         ... # perform completion for foo
                       fi
                       ... # test the tags bar and baz in the same way
                       ... # exit loop if matches were generated
                     done

              Note  that  the  test  for whether matches were generated is not
              performed until the end of the _tags loop.  This is so that  the
              user  can set the tag-order style to specify a set of tags to be
              completed at the same time.

              If name and descr are given, _requested calls  the  _description
              function  with  these arguments together with the options passed
              to _requested.

              If command is given, the _all_labels  function  will  be  called
              immediately with the same arguments.  In simple cases this makes
              it possible to perform the test for the tag and the matching  in
              one go.  For example:

                     local expl ret=1
                     _tags foo bar baz
                     while _tags; do
                       _requested foo expl 'description' \
                           compadd foobar foobaz && ret=0
                       ...
                       (( ret )) || break
                     done

              If  the command is not compadd, it must nevertheless be prepared
              to handle the same options.

       _retrieve_cache cache_identifier
              This function retrieves completion  information  from  the  file
              given  by  cache_identifier,  stored in a directory specified by
              the cache-path  style  which  defaults  to  ~/.zcompcache.   The
              return status is zero if retrieval was successful.  It will only
              attempt retrieval if the use-cache style is set, so you can call
              this  function without worrying about whether the user wanted to
              use the caching layer.

              See _store_cache below for more details.

       _sep_parts
              This function is passed alternating  arrays  and  separators  as
              arguments.   The arrays specify completions for parts of strings
              to be separated by the separators.  The arrays may be the  names
              of  array  parameters  or a quoted list of words in parentheses.
              For  example,  with  the  array  `hosts=(ftp  news)'  the   call
              `_sep_parts  '(foo  bar)' @ hosts' will complete the string  `f'
              to `foo' and the string `b@n' to `bar@news'.

              This function accepts the  compadd  options  `-V',  `-J',  `-1',
              `-2',  `-n',  `-X',  `-M',  `-P', `-S', `-r', `-R', and `-q' and
              passes them on to the compadd builtin used to add the matches.

       _sequence [ -s sep ] [ -n max ] [ -d ] function [ - ] ...
              This function is a wrapper to  other  functions  for  completing
              items in a separated list. The same function is used to complete
              each item in the list. The separator is specified  with  the  -s
              option.  If  -s is omitted it will use `,'. Duplicate values are
              not matched unless -d is specified. If there is a fixed or maxi-
              mum  number of items in the list, this can be specified with the
              -n option.

              Common compadd options are passed on to the function. It is pos-
              sible to use compadd directly with _sequence, though _values may
              be more appropriate in this situation.

       _setup tag [ group ]
              This function sets up the special parameters used by the comple-
              tion  system  appropriately for the tag given as the first argu-
              ment.    It   uses   the   styles   list-colors,    list-packed,
              list-rows-first, last-prompt, accept-exact, menu and force-list.

              The  optional  group supplies the name of the group in which the
              matches will be placed.  If it is not given, the tag is used  as
              the group name.

              This  function  is  called  automatically  from _description and
              hence is not normally called explicitly.

       _store_cache cache_identifier param ...
              This function, together with _retrieve_cache and _cache_invalid,
              implements  a  caching layer which can be used in any completion
              function.  Data obtained by  costly  operations  are  stored  in
              parameters; this function then dumps the values of those parame-
              ters to a file.  The data can then  be  retrieved  quickly  from
              that  file  via  _retrieve_cache, even in different instances of
              the shell.

              The cache_identifier specifies the file which the data should be
              dumped  to.   The file is stored in a directory specified by the
              cache-path style which defaults to ~/.zcompcache.  The remaining
              params arguments are the parameters to dump to the file.

              The  return status is zero if storage was successful.  The func-
              tion will only attempt storage if the use-cache style is set, so
              you  can  call  this function without worrying about whether the
              user wanted to use the caching layer.

              The completion function may avoid calling  _retrieve_cache  when
              it  already  has  the  completion  data available as parameters.
              However, in that case it should  call  _cache_invalid  to  check
              whether  the  data  in the parameters and in the cache are still
              valid.

              See the _perl_modules completion function for a  simple  example
              of the usage of the caching layer.

       _tags [ [ -C name ] tag ... ]
              If  called  with  arguments,  these are taken to be the names of
              tags valid for completions in the current context.   These  tags
              are stored internally and sorted by using the tag-order style.

              Next, _tags is called repeatedly without arguments from the same
              completion function.  This successively selects the first,  sec-
              ond,  etc. set of tags requested by the user.  The return status
              is zero if at least one of the tags is  requested  and  non-zero
              otherwise.   To  test  if  a  particular tag is to be tried, the
              _requested function should be called (see above).

              If `-C name' is given, name is temporarily stored in  the  argu-
              ment  field (the fifth) of the context in the curcontext parame-
              ter during the call to _tags; the field  is  restored  on  exit.
              This  allows _tags to use a more specific context without having
              to change and reset the curcontext parameter (which has the same
              effect).

       _tilde_files
              Like  _files,  but resolve leading tildes according to the rules
              of filename expansion, so the suggested completions don't  start
              with a `~' even if the filename on the command-line does.

       _values [ -O name ] [ -s sep ] [ -S sep ] [ -wC ] desc spec ...
              This  is  used to complete arbitrary keywords (values) and their
              arguments, or lists of such combinations.

              If the first argument is the option `-O name', it will  be  used
              in  the same way as by the _arguments function.  In other words,
              the elements of the name array will be passed  to  compadd  when
              executing an action.

              If the first argument (or the first argument after `-O name') is
              `-s', the next argument is used as the character that  separates
              multiple  values.   This  character is automatically added after
              each value in an auto-removable fashion (see below); all  values
              completed by `_values -s' appear in the same word on the command
              line, unlike completion using _arguments.  If this option is not
              present, only a single value will be completed per word.

              Normally,  _values  will  only use the current word to determine
              which values are already present on the command line  and  hence
              are not to be completed again.  If the -w option is given, other
              arguments are examined as well.

              The first non-option argument is used as a string to print as  a
              description before listing the values.

              All other arguments describe the possible values and their argu-
              ments in the same format used for the description of options  by
              the  _arguments  function (see above).  The only differences are
              that no minus or plus sign is required at the beginning,  values
              can  have  only  one argument, and the forms of action beginning
              with an equal sign are not supported.

              The character separating a value from its argument  can  be  set
              using  the  option -S (like -s, followed by the character to use
              as the separator in the next argument).  By default  the  equals
              sign will be used as the separator between values and arguments.

              Example:

                     _values -s , 'description' \
                             '*foo[bar]' \
                             '(two)*one[number]:first count:' \
                             'two[another number]::second count:(1 2 3)'

              This  describes  three possible values: `foo', `one', and `two'.
              The first is described as  `bar',  takes  no  argument  and  may
              appear more than once.  The second is described as `number', may
              appear  more  than  once,  and  takes  one  mandatory   argument
              described  as  `first count'; no action is specified, so it will
              not be completed.  The `(two)' at the beginning says that if the
              value  `one'  is  on the line, the value `two' will no longer be
              considered a  possible  completion.   Finally,  the  last  value
              (`two')  is  described as `another number' and takes an optional
              argument described as `second count' for which  the  completions
              (to  appear  after  an  `=') are `1', `2', and `3'.  The _values
              function will complete lists of these values separated  by  com-
              mas.

              Like  _arguments, this function temporarily adds another context
              name component to the arguments element (the fifth) of the  cur-
              rent context while executing the action.  Here this name is just
              the name of the value for which the argument is completed.

              The style verbose is used to decide if the descriptions for  the
              values (but not those for the arguments) should be printed.

              The  associative  array  val_args  is  used to report values and
              their arguments; this works similarly to the  opt_args  associa-
              tive array used by _arguments.  Hence the function calling _val-
              ues should declare  the  local  parameters  state,  state_descr,
              line, context and val_args:

                     local context state state_descr line
                     typeset -A val_args

              when using an action of the form `->string'.  With this function
              the context parameter will be set to the name of the value whose
              argument  is  to be completed.  Note that for _values, the state
              and state_descr are scalars rather than arrays.  Only  a  single
              matching state is returned.

              Note  also  that _values normally adds the character used as the
              separator between values as an auto-removable suffix (similar to
              a  `/'  after a directory).  However, this is not possible for a
              `->string' action as the matches for the argument are  generated
              by  the calling function.  To get the usual behaviour, the call-
              ing function can add the separator x as a suffix by passing  the
              options `-qS x' either directly or indirectly to compadd.

              The option -C is treated in the same way as it is by _arguments.
              In that case the  parameter  curcontext  should  be  made  local
              instead of context (as described above).

       _wanted [ -x ] [ -C name ]  [ -12VJ ] tag name descr command [ arg ...]
              In  many  contexts,  completion can only generate one particular
              set of matches, usually corresponding to a single tag.  However,
              it  is  still  necessary  to  decide  whether  the user requires
              matches of this type.  This function is useful in such a case.

              The arguments to _wanted are the same as  those  to  _requested,
              i.e.  arguments  to be passed to _description.  However, in this
              case the command is not optional;  all the processing  of  tags,
              including the loop over both tags and tag labels and the genera-
              tion of matches, is carried out automatically by _wanted.

              Hence to offer only one tag and immediately add the  correspond-
              ing matches with the given description:

                     local expl
                     _wanted tag expl 'description' \
                         compadd matches...

              Note that, as for _requested, the command must be able to accept
              options to be passed down to compadd.

              Like _tags this function supports the -C option to give  a  dif-
              ferent  name  for the argument context field.  The -x option has
              the same meaning as for _description.

       _widgets [ -g pattern ]
              This function completes names of zle widgets  (see  the  section
              `Widgets'  in  zshzle(1)).   The pattern, if present, is matched
              against values of the $widgets special parameter, documented  in
              the section `The zsh/zleparameter Module' in zshmodules(1).

COMPLETION SYSTEM VARIABLES
       There  are  some  standard variables, initialised by the _main_complete
       function and then used from other functions.

       The standard variables are:

       _comp_caller_options
              The completion system uses setopt to set a  number  of  options.
              This allows functions to be written without concern for compati-
              bility with every possible combination of user options. However,
              sometimes  completion needs to know what the user's option pref-
              erences are. These are saved in the  _comp_caller_options  asso-
              ciative array. Option names, spelled in lowercase without under-
              scores, are mapped to one or  other  of  the  strings  `on'  and
              `off'.

              _comp_priv_prefix
                     Completion   functions   such   as   _sudo  can  set  the
                     _comp_priv_prefix array to a command prefix that may then
                     be  used  by  _call_program  to match the privileges when
                     calling programs to generate matches.

              Two more features are offered by  the  _main_complete  function.
              The  arrays  compprefuncs and comppostfuncs may contain names of
              functions that are to be called immediately before or after com-
              pletion  has  been  tried.   A function will only be called once
              unless it explicitly reinserts itself into the array.

COMPLETION DIRECTORIES
       In the source distribution, the files are contained in  various  subdi-
       rectories of the Completion directory.  They may have been installed in
       the same structure, or into one single function directory.  The follow-
       ing  is  a  description  of  the  files found in the original directory
       structure.  If you wish to alter an installed file, you  will  need  to
       copy  it to some directory which appears earlier in your fpath than the
       standard directory where it appears.

       Base   The core functions and special completion widgets  automatically
              bound  to  keys.   You will certainly need most of these, though
              will probably not need to alter them.  Many of these  are  docu-
              mented above.

       Zsh    Functions for completing arguments of shell builtin commands and
              utility functions for this.  Some of  these  are  also  used  by
              functions from the Unix directory.

       Unix   Functions  for  completing  arguments  of  external commands and
              suites of commands.  They may need modifying  for  your  system,
              although in many cases some attempt is made to decide which ver-
              sion of a command is present.  For example, completion  for  the
              mount  command  tries  to determine the system it is running on,
              while completion for many other utilities try to decide  whether
              the  GNU version of the command is in use, and hence whether the
              --help option is supported.

       X, AIX, BSD, ...
              Completion and utility function for commands available  only  on
              some  systems.   These  are not arranged hierarchically, so, for
              example, both the Linux and Debian directories, as well as the X
              directory, may be useful on your system.



ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+------------------+
       |ATTRIBUTE TYPE | ATTRIBUTE VALUE  |
       +---------------+------------------+
       |Availability   | shell/zsh        |
       +---------------+------------------+
       |Stability      | Volatile         |
       +---------------+------------------+
NOTES
       This     software     was    built    from    source    available    at
       https://github.com/oracle/solaris-userland.   The  original   community
       source      was      downloaded     from      https://downloads.source-
       forge.net/project/zsh/zsh/5.3.1/zsh-5.3.1.tar.xz

       Further information about this software can be found on the open source
       community website at https://www.zsh.org/.



zsh 5.3.1                      December 21, 2016                 ZSHCOMPSYS(1)