man pages section 1: User Commands

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Updated: July 2014

tcsh (1)


tcsh - C shell with file name completion and command line editing


tcsh [-bcdefFimnqstvVxX] [-Dname[=value]] [arg ...]
tcsh -l


User Commands                                             TCSH(1)

     tcsh  -  C  shell with file name completion and command line

     tcsh [-bcdefFimnqstvVxX] [-Dname[=value]] [arg ...]
     tcsh -l

     tcsh is an enhanced but completely compatible version of the
     Berkeley  UNIX  C  shell,  csh(1).  It is a command language
     interpreter usable both as an interactive login shell and  a
     shell  script command processor.  It includes a command-line
     editor (see The command-line editor), programmable word com-
     pletion  (see  Completion  and listing), spelling correction
     (see Spelling correction), a history mechanism (see  History
     substitution),  job  control (see Jobs) and a C-like syntax.
     The NEW FEATURES section  describes  major  enhancements  of
     tcsh  over csh(1).  Throughout this manual, features of tcsh
     not found in most csh(1) implementations (specifically,  the
     4.4BSD  csh)  are labeled with `(+)', and features which are
     present in csh(1) but not  usually  documented  are  labeled
     with `(u)'.

  Argument list processing
     If  the first argument (argument 0) to the shell is `-' then
     it is a login shell.  A login shell can be also specified by
     invoking the shell with the -l flag as the only argument.

     The rest of the flag arguments are interpreted as follows:

     -b  Forces  a  ``break'' from option processing, causing any
         further shell arguments  to  be  treated  as  non-option
         arguments.   The  remaining arguments will not be inter-
         preted as shell options.   This  may  be  used  to  pass
         options  to a shell script without confusion or possible
         subterfuge.  The shell will not run a set-user ID script
         without this option.

     -c  Commands  are  read  from  the following argument (which
         must be present, and must be a single argument),  stored
         in  the  command  shell variable for reference, and exe-
         cuted.  Any remaining arguments are placed in  the  argv
         shell variable.

     -d  The  shell  loads the directory stack from ~/.cshdirs as
         described under Startup and shutdown, whether or not  it
         is a login shell. (+)

         Sets  the environment variable name to value. (Domain/OS
         only) (+)

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     -e  The shell exits if any invoked command terminates abnor-
         mally or yields a non-zero exit status.

     -f  The  shell  does not load any resource or startup files,
         or perform any command hashing, and thus starts  faster.

     -F  The shell uses fork(2) instead of vfork(2) to spawn pro-
         cesses. (+)

     -i  The shell is interactive and prompts for  its  top-level
         input,  even if it appears to not be a terminal.  Shells
         are interactive without this option if their inputs  and
         outputs are terminals.

     -l  The  shell  is  a login shell.  Applicable only if -l is
         the only flag specified.

     -m  The shell loads ~/.tcshrc even if it does not belong  to
         the  effective  user.  Newer versions of su(1M) can pass
         -m to the shell. (+)

     -n  The shell parses commands but  does  not  execute  them.
         This aids in debugging shell scripts.

     -q  The  shell  accepts  SIGQUIT  (see  Signal handling) and
         behaves when it is used under a debugger.   Job  control
         is disabled. (u)

     -s  Command input is taken from the standard input.

     -t  The  shell reads and executes a single line of input.  A
         `\' may be used to escape the newline at the end of this
         line and continue onto another line.

     -v  Sets  the  verbose shell variable, so that command input
         is echoed after history substitution.

     -x  Sets the echo  shell  variable,  so  that  commands  are
         echoed immediately before execution.

     -V  Sets  the  verbose  shell variable even before executing

     -X  Is to -x as -V is to -v.

         Print a help message on the standard  output  and  exit.

         Print  the  version/platform/compilation  options on the
         standard output and  exit.   This  information  is  also

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         contained in the version shell variable. (+)

     After  processing of flag arguments, if arguments remain but
     none of the -c, -i, -s, or -t options were given, the  first
     argument  is  taken  as  the  name of a file of commands, or
     ``script'', to be executed.  The shell opens this  file  and
     saves its name for possible resubstitution by `$0'.  Because
     many systems use either the standard version 6 or version  7
     shells  whose  shell  scripts  are  not compatible with this
     shell, the shell uses such a `standard' shell to  execute  a
     script  whose  first character is not a `#', i.e., that does
     not start with a comment.

     Remaining arguments are placed in the argv shell variable.

  Startup and shutdown
     A login shell begins by executing commands from  the  system
     files  /etc/.cshrc  and  /etc/.login.  It then executes com-
     mands  from  files  in  the  user's  home  directory:  first
     ~/.tcshrc  (+) or, if ~/.tcshrc is not found, ~/.cshrc, then
     ~/.history (or the value of the  histfile  shell  variable),
     then  ~/.login,  and finally ~/.cshdirs (or the value of the
     dirsfile  shell  variable)  (+).    The   shell   may   read
     /etc/csh.login  before  instead  of  after  /etc/.cshrc, and
     ~/.login before instead of after ~/.tcshrc or  ~/.cshrc  and
     ~/.history,  if so compiled; see the version shell variable.

     Non-login shells read  only  /etc/.cshrc  and  ~/.tcshrc  or
     ~/.cshrc on startup.

     For    examples    of    startup   files,   please   consult

     Commands like stty(1) and tset(1B), which need be  run  only
     once  per  login,  usually go in one's ~/.login file.  Users
     who need to use the same set of files with both  csh(1)  and
     tcsh can have only a ~/.cshrc which checks for the existence
     of the tcsh shell variable (q.v.) before using tcsh-specific
     commands,  or can have both a ~/.cshrc and a ~/.tcshrc which
     sources (see the builtin command)  ~/.cshrc.   The  rest  of
     this  manual  uses  `~/.tcshrc'  to  mean  `~/.tcshrc or, if
     ~/.tcshrc is not found, ~/.cshrc'.

     In the normal case, the shell begins reading  commands  from
     the terminal, prompting with `> '.  (Processing of arguments
     and the use of the shell to process files containing command
     scripts  are described later.)  The shell repeatedly reads a
     line of command input, breaks it into words,  places  it  on
     the  command  history list, parses it and executes each com-
     mand in the line.

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     One can log out by typing `^D' on an empty line, `logout' or
     `login'  or  via  the  shell's autologout mechanism (see the
     autologout shell variable).  When a login  shell  terminates
     it sets the logout shell variable to `normal' or `automatic'
     as  appropriate,  then  executes  commands  from  the  files
     /etc/csh.logout  and  ~/.logout.   The shell may drop DTR on
     logout if so compiled; see the version shell variable.

     The names of the system login and  logout  files  vary  from
     system  to  system  for  compatibility with different csh(1)
     variants; see FILES.

     We first describe The command-line editor.   The  Completion
     and  listing  and  Spelling correction sections describe two
     sets of functionality that are implemented  as  editor  com-
     mands  but which deserve their own treatment.  Finally, Edi-
     tor commands lists and describes the  editor  commands  spe-
     cific to the shell and their default bindings.

  The command-line editor (+)
     Command-line  input  can  be edited using key sequences much
     like those used in GNU Emacs or vi(1).  The editor is active
     only  when  the  edit  shell variable is set, which it is by
     default in interactive shells.  The bindkey builtin can dis-
     play  and change key bindings.  Emacs-style key bindings are
     used by default (unless the shell  was  compiled  otherwise;
     see  the version shell variable), but bindkey can change the
     key bindings to vi-style bindings en masse.

     The shell always binds the arrow keys  (as  defined  in  the
     TERMCAP environment variable) to

         down    down-history
         up      up-history
         left    backward-char
         right   forward-char

     unless  doing  so would alter another single-character bind-
     ing.  One can set the arrow  key  escape  sequences  to  the
     empty  string  with  settc  to  prevent these bindings.  The
     ANSI/VT100 sequences for arrow keys are always bound.

     Other key bindings are, for the most part,  what  Emacs  and
     vi(1)  users  would  expect  and  can easily be displayed by
     bindkey, so there is no need to list them  here.   Likewise,
     bindkey  can  list the editor commands with a short descrip-
     tion of each.

     Note that editor commands do not have the same notion  of  a
     ``word''  as does the shell.  The editor delimits words with
     any non-alphanumeric characters not in  the  shell  variable

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User Commands                                             TCSH(1)

     wordchars,  while  the  shell recognizes only whitespace and
     some of the characters with special meanings to  it,  listed
     under Lexical structure.

  Completion and listing (+)
     The  shell  is  often  able  to  complete words when given a
     unique abbreviation.  Type part of a word (for  example  `ls
     /usr/lost')  and  hit  the  tab key to run the complete-word
     editor  command.    The   shell   completes   the   filename
     `/usr/lost'  to `/usr/lost+found/', replacing the incomplete
     word with the complete word in the input buffer.  (Note  the
     terminal  `/'; completion adds a `/' to the end of completed
     directories and a space to the end of other completed words,
     to speed typing and provide a visual indicator of successful
     completion.  The addsuffix shell variable can  be  unset  to
     prevent    this.)    If   no   match   is   found   (perhaps
     `/usr/lost+found' doesn't exist), the terminal  bell  rings.
     If  the  word  is  already  complete  (perhaps  there  is  a
     `/usr/lost' on your system, or perhaps you were thinking too
     far ahead and typed the whole thing) a `/' or space is added
     to the end if it isn't already there.

     Completion works anywhere in the line, not at just the  end;
     completed  text  pushes  the  rest of the line to the right.
     Completion in the middle of a word often results in leftover
     characters  to  the  right  of  the  cursor  that need to be

     Commands and variables can be completed  in  much  the  same
     way.   For  example, typing `em[tab]' would complete `em' to
     `emacs' if emacs were the only command on your system begin-
     ning with `em'.  Completion can find a command in any direc-
     tory in path or if given  a  full  pathname.   Typing  `echo
     $ar[tab]'  would complete `$ar' to `$argv' if no other vari-
     able began with `ar'.

     The shell parses the input buffer to determine  whether  the
     word you want to complete should be completed as a filename,
     command or variable.  The first word in the buffer  and  the
     first word following `;', `|', `|&', `&&' or `||' is consid-
     ered to be a command.  A word beginning with `$' is  consid-
     ered  to  be  a  variable.  Anything else is a filename.  An
     empty line is `completed' as a filename.

     You can list the possible completions of a word at any  time
     by  typing `^D' to run the delete-char-or-list-or-eof editor
     command.  The shell lists the possible completions using the
     ls-F  builtin (q.v.)  and reprints the prompt and unfinished
     command line, for example:

         > ls /usr/l[^D]
         lbin/       lib/        local/      lost+found/

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User Commands                                             TCSH(1)

         > ls /usr/l

     If the autolist shell variable is set, the shell  lists  the
     remaining choices (if any) whenever completion fails:

         > set autolist
         > nm /usr/lib/libt[tab]
         libtermcap.a@ libtermlib.a@
         > nm /usr/lib/libterm

     If  autolist  is set to `ambiguous', choices are listed only
     when completion fails and adds no new characters to the word
     being completed.

     A  filename  to be completed can contain variables, your own
     or others' home directories abbreviated with `~' (see  File-
     name  substitution)  and directory stack entries abbreviated
     with `=' (see Directory stack substitution).  For example,

         > ls ~k[^D]
         kahn    kas     kellogg
         > ls ~ke[tab]
         > ls ~kellogg/


         > set local = /usr/local
         > ls $lo[tab]
         > ls $local/[^D]
         bin/ etc/ lib/ man/ src/
         > ls $local/

     Note that variables can also be expanded explicitly with the
     expand-variables editor command.

     delete-char-or-list-or-eof  lists  at  only  the  end of the
     line; in the middle of a line it deletes the character under
     the  cursor  and  on  an  empty  line it logs one out or, if
     ignoreeof is set, does nothing.  `M-^D', bound to the editor
     command  list-choices,  lists  completion possibilities any-
     where on a line, and list-choices (or any one of the related
     editor  commands  that  do  or don't delete, list and/or log
     out, listed under delete-char-or-list-or-eof) can  be  bound
     to `^D' with the bindkey builtin command if so desired.

     The complete-word-fwd and complete-word-back editor commands
     (not bound to any keys by default) can be used to  cycle  up
     and down through the list of possible completions, replacing
     the current word with the next or previous word in the list.

     The  shell variable fignore can be set to a list of suffixes
     to be ignored by completion.  Consider the following:

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User Commands                                             TCSH(1)

         > ls
         Makefile        condiments.h~   main.o          side.c
         README          main.c          meal            side.o
         condiments.h    main.c~
         > set fignore = (.o \~)
         > emacs ma[^D]
         main.c   main.c~  main.o
         > emacs ma[tab]
         > emacs main.c

     `main.c~' and `main.o' are ignored by  completion  (but  not
     listing),  because  they  end  in suffixes in fignore.  Note
     that a `\' was needed in front of `~'  to  prevent  it  from
     being expanded to home as described under Filename substitu-
     tion.  fignore is ignored if only one completion  is  possi-

     If  the complete shell variable is set to `enhance', comple-
     tion 1) ignores case and 2) considers periods,  hyphens  and
     underscores  (`.',  `-'  and  `_') to be word separators and
     hyphens and underscores to be equivalent.  If  you  had  the
     following files

         comp.lang.c      comp.lang.perl   comp.std.c++
         comp.lang.c++    comp.std.c

     and  typed  `mail  -f  c.l.c[tab]', it would be completed to
     `mail -f comp.lang.c', and ^D would list  `comp.lang.c'  and
     `comp.lang.c++'.     `mail   -f   c..c++[^D]'   would   list
     `comp.lang.c++' and `comp.std.c++'.  Typing `rm a--file[^D]'
     in the following directory

         A_silly_file    a-hyphenated-file    another_silly_file

     would  list  all  three  files,  because case is ignored and
     hyphens and underscores are equivalent.   Periods,  however,
     are not equivalent to hyphens or underscores.

     If  the complete shell variable is set to `Enhance', comple-
     tion ignores case and differences between a  hyphen  and  an
     underscore  word separator only when the user types a lower-
     case character or a hyphen.  Entering an uppercase character
     or  an underscore will not match the corresponding lowercase
     character or hyphen word separator.  Typing `rm a--file[^D]'
     in  the  directory  of the previous example would still list
     all three files, but typing `rm A--file'  would  match  only
     `A_silly_file'  and typing `rm a__file[^D]' would match just
     `A_silly_file' and  `another_silly_file'  because  the  user
     explicitly used an uppercase or an underscore character.

     Completion  and  listing are affected by several other shell
     variables: recexact can be set to complete on  the  shortest

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     possible unique match, even if more typing might result in a
     longer match:

         > ls
         fodder   foo      food     foonly
         > set recexact
         > rm fo[tab]

     just beeps, because `fo' could expand to `fod' or `foo', but
     if we type another `o',

         > rm foo[tab]
         > rm foo

     the  completion  completes  on `foo', even though `food' and
     `foonly' also match.  autoexpand  can  be  set  to  run  the
     expand-history   editor   command   before  each  completion
     attempt, autocorrect can be set to spelling-correct the word
     to  be  completed (see Spelling correction) before each com-
     pletion attempt and correct can be set to complete  commands
     automatically after one hits `return'.  matchbeep can be set
     to make completion beep or not beep in a variety  of  situa-
     tions,  and  nobeep can be set to never beep at all.  nostat
     can be set to a list of  directories  and/or  patterns  that
     match  directories  to prevent the completion mechanism from
     stat(2)ing those directories.  listmax and  listmaxrows  can
     be  set to limit the number of items and rows (respectively)
     that are listed without asking  first.   recognize_only_exe-
     cutables  can be set to make the shell list only executables
     when listing commands, but it is quite slow.

     Finally, the complete builtin command can be  used  to  tell
     the  shell  how to complete words other than filenames, com-
     mands and variables.  Completion and listing do not work  on
     glob-patterns (see Filename substitution), but the list-glob
     and expand-glob editor commands perform equivalent functions
     for glob-patterns.

  Spelling correction (+)
     The  shell  can sometimes correct the spelling of filenames,
     commands and variable names as well as completing and  list-
     ing them.

     Individual  words  can be spelling-corrected with the spell-
     word editor command (usually bound to M-s and M-S)  and  the
     entire  input buffer with spell-line (usually bound to M-$).
     The correct shell variable can be set to  `cmd'  to  correct
     the  command  name  or `all' to correct the entire line each
     time return is typed, and autocorrect can be set to  correct
     the word to be completed before each completion attempt.

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     When spelling correction is invoked in any of these ways and
     the shell thinks that any part of the command line  is  mis-
     spelled, it prompts with the corrected line:

         > set correct = cmd
         > lz /usr/bin
         CORRECT>ls /usr/bin (y|n|e|a)?

     One  can  answer `y' or space to execute the corrected line,
     `e' to leave the uncorrected command in  the  input  buffer,
     `a'  to  abort the command as if `^C' had been hit, and any-
     thing else to execute the original line unchanged.

     Spelling correction recognizes user-defined completions (see
     the  complete builtin command).  If an input word in a posi-
     tion for which a completion is defined resembles a  word  in
     the  completion  list,  spelling correction registers a mis-
     spelling and suggests the latter word as a correction.  How-
     ever,  if  the input word does not match any of the possible
     completions for that position, spelling correction does  not
     register a misspelling.

     Like  completion,  spelling correction works anywhere in the
     line, pushing the rest of the line to the right and possibly
     leaving extra characters to the right of the cursor.

     Beware:  spelling  correction  is not guaranteed to work the
     way one intends, and is provided mostly as  an  experimental
     feature.  Suggestions and improvements are welcome.

  Editor commands (+)
     `bindkey'  lists  key  bindings  and  `bindkey -l' lists and
     briefly describes editor commands.  Only new  or  especially
     interesting   editor   commands  are  described  here.   See
     emacs(1) and vi(1) for descriptions  of  each  editor's  key

     The  character  or characters to which each command is bound
     by default is given in parentheses.   `^character'  means  a
     control  character and `M-character' a meta character, typed
     as escape-character on terminals without a meta  key.   Case
     counts,  but  commands  that are bound to letters by default
     are bound to both lower- and uppercase  letters  for  conve-

     complete-word (tab)
             Completes  a  word as described under Completion and

     complete-word-back (not bound)
             Like complete-word-fwd, but steps up from the end of
             the list.

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     complete-word-fwd (not bound)
             Replaces the current word with the first word in the
             list of possible completions.  May  be  repeated  to
             step down through the list.  At the end of the list,
             beeps and reverts to the incomplete word.

     complete-word-raw (^X-tab)
             Like complete-word, but ignores user-defined comple-

     copy-prev-word (M-^_)
             Copies  the  previous  word in the current line into
             the input buffer.  See also insert-last-word.

     dabbrev-expand (M-/)
             Expands the current word to the most recent  preced-
             ing  one  for  which  the  current is a leading sub-
             string, wrapping around the history list  (once)  if
             necessary.   Repeating  dabbrev-expand  without  any
             intervening typing changes to the next previous word
             etc.,  skipping identical matches much like history-
             search-backward does.

     delete-char (not bound)
             Deletes the character under the  cursor.   See  also

     delete-char-or-eof (not bound)
             Does  delete-char  if there is a character under the
             cursor or end-of-file on an empty  line.   See  also

     delete-char-or-list (not bound)
             Does  delete-char  if there is a character under the
             cursor or list-choices at the end of the line.   See
             also delete-char-or-list-or-eof.

     delete-char-or-list-or-eof (^D)
             Does  delete-char  if there is a character under the
             cursor, list-choices at the end of the line or  end-
             of-file on an empty line.  See also those three com-
             mands, each of which does only a single action,  and
             delete-char-or-eof, delete-char-or-list and list-or-
             eof, each of which does a different two out  of  the

     down-history (down-arrow, ^N)
             Like  up-history,  but  steps  down, stopping at the
             original input line.

     end-of-file (not bound)
             Signals an end of file, causing the  shell  to  exit

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             unless the ignoreeof shell variable (q.v.) is set to
             prevent this.  See also  delete-char-or-list-or-eof.

     expand-history (M-space)
             Expands  history  substitutions in the current word.
             See History  substitution.   See  also  magic-space,
             toggle-literal-history   and  the  autoexpand  shell

     expand-glob (^X-*)
             Expands the glob-pattern to the left of the  cursor.
             See Filename substitution.

     expand-line (not bound)
             Like  expand-history,  but expands history substitu-
             tions in each word in the input buffer.

     expand-variables (^X-$)
             Expands the variable to the left of the cursor.  See
             Variable substitution.

     history-search-backward (M-p, M-P)
             Searches  backwards  through  the history list for a
             command beginning with the current contents  of  the
             input buffer up to the cursor and copies it into the
             input buffer.  The search string may be a  glob-pat-
             tern  (see  Filename  substitution)  containing `*',
             `?', `[]' or `{}'.  up-history and down-history will
             proceed  from  the  appropriate point in the history
             list.  Emacs mode only.   See  also  history-search-
             forward and i-search-back.

     history-search-forward (M-n, M-N)
             Like  history-search-backward, but searches forward.

     i-search-back (not bound)
             Searches  backward   like   history-search-backward,
             copies  the  first  match into the input buffer with
             the cursor positioned at the end of the pattern, and
             prompts  with  `bck:  '  and the first match.  Addi-
             tional characters may be typed to extend the search,
             i-search-back  may  be  typed  to continue searching
             with the same pattern, wrapping around  the  history
             list if necessary, (i-search-back must be bound to a
             single character for this to work)  or  one  of  the
             following special characters may be typed:

                 ^W      Appends  the  rest of the word under the
                         cursor to the search pattern.
                 delete (or any character  bound  to  backward-

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                         Undoes the effect of the last  character
                         typed  and  deletes a character from the
                         search pattern if appropriate.
                 ^G      If the previous search  was  successful,
                         aborts  the entire search.  If not, goes
                         back to the last successful search.
                 escape  Ends the  search,  leaving  the  current
                         line in the input buffer.

             Any other character not bound to self-insert-command
             terminates the search, leaving the current  line  in
             the  input buffer, and is then interpreted as normal
             input.  In particular, a carriage return causes  the
             current  line to be executed.  Emacs mode only.  See
             also i-search-fwd and history-search-backward.

     i-search-fwd (not bound)
             Like i-search-back, but searches forward.

     insert-last-word (M-_)
             Inserts the last word of  the  previous  input  line
             (`!$')  into  the input buffer.  See also copy-prev-

     list-choices (M-^D)
             Lists completion possibilities  as  described  under
             Completion  and  listing.   See also delete-char-or-
             list-or-eof and list-choices-raw.

     list-choices-raw (^X-^D)
             Like list-choices, but ignores user-defined  comple-

     list-glob (^X-g, ^X-G)
             Lists  (via  the  ls-F builtin) matches to the glob-
             pattern (see Filename substitution) to the  left  of
             the cursor.

     list-or-eof (not bound)
             Does  list-choices  or end-of-file on an empty line.
             See also delete-char-or-list-or-eof.

     magic-space (not bound)
             Expands history substitutions in the  current  line,
             like  expand-history,  and  inserts a space.  magic-
             space is designed to be bound to the space bar,  but
             is not bound by default.

     normalize-command (^X-?)
             Searches  for the current word in PATH and, if it is
             found, replaces it with the full path  to  the  exe-
             cutable.   Special  characters  are quoted.  Aliases

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User Commands                                             TCSH(1)

             are expanded and quoted but commands within  aliases
             are  not.  This command is useful with commands that
             take commands as arguments, e.g., `dbx' and `sh -x'.

     normalize-path (^X-n, ^X-N)
             Expands  the  current  word  as  described under the
             `expand' setting of the symlinks shell variable.

     overwrite-mode (unbound)
             Toggles between input and overwrite modes.

     run-fg-editor (M-^Z)
             Saves the current input line and looks for a stopped
             job  with  a name equal to the last component of the
             file name part of the EDITOR or  VISUAL  environment
             variables,  or, if neither is set, `ed' or `vi'.  If
             such a job is found, it is restarted as if `fg %job'
             had  been  typed.   This  is used to toggle back and
             forth between an editor and the shell easily.   Some
             people bind this command to `^Z' so they can do this
             even more easily.

     run-help (M-h, M-H)
             Searches for documentation on the  current  command,
             using  the  same  notion of `current command' as the
             completion routines, and prints it.  There is no way
             to  use a pager; run-help is designed for short help
             files.  If the special alias helpcommand is defined,
             it  is run with the command name as a sole argument.
             Else, documentation should be in a file  named  com-
   ,  command.1,  command.6, command.8 or com-
             mand, which should be  in  one  of  the  directories
             listed  in the HPATH environment variable.  If there
             is more  than  one  help  file  only  the  first  is

     self-insert-command (text characters)
             In  insert  mode  (the  default),  inserts the typed
             character into the input line  after  the  character
             under  the  cursor.  In overwrite mode, replaces the
             character under the cursor with the typed character.
             The  input mode is normally preserved between lines,
             but the inputmode  shell  variable  can  be  set  to
             `insert'  or  `overwrite'  to put the editor in that
             mode at the beginning of each line.  See also  over-

     sequence-lead-in (arrow prefix, meta prefix, ^X)
             Indicates  that the following characters are part of
             a multi-key sequence.  Binding a command to a multi-
             key  sequence really creates two bindings: the first
             character to sequence-lead-in and the whole sequence

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User Commands                                             TCSH(1)

             to  the  command.   All  sequences  beginning with a
             character bound to sequence-lead-in are  effectively
             bound  to undefined-key unless bound to another com-

     spell-line (M-$)
             Attempts to correct the spelling of each word in the
             input  buffer,  like  spell-word,  but ignores words
             whose first character is one of  `-',  `!',  `^'  or
             `%',  or  which  contain  `\',  `*' or `?', to avoid
             problems with switches, substitutions and the  like.
             See Spelling correction.

     spell-word (M-s, M-S)
             Attempts to correct the spelling of the current word
             as described under Spelling correction.  Checks each
             component  of a word which appears to be a pathname.

     toggle-literal-history (M-r, M-R)
             Expands or `unexpands' history substitutions in  the
             input buffer.  See also expand-history and the auto-
             expand shell variable.

     undefined-key (any unbound key)

     up-history (up-arrow, ^P)
             Copies the previous entry in the history  list  into
             the  input buffer.  If histlit is set, uses the lit-
             eral form of the entry.  May be repeated to step  up
             through the history list, stopping at the top.

     vi-search-back (?)
             Prompts with `?' for a search string (which may be a
             glob-pattern,  as   with   history-search-backward),
             searches for it and copies it into the input buffer.
             The bell rings if no match is found.  Hitting return
             ends  the  search  and  leaves the last match in the
             input buffer.  Hitting escape ends  the  search  and
             executes the match.  vi mode only.

     vi-search-fwd (/)
             Like vi-search-back, but searches forward.

     which-command (M-?)
             Does  a  which  (see  the description of the builtin
             command) on the first word of the input buffer.

     yank-pop (M-y)
             When executed immediately after a  yank  or  another
             yank-pop,  replaces  the yanked string with the next
             previous string from the killring. This also has the

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User Commands                                             TCSH(1)

             effect  of  rotating  the  killring,  such that this
             string will be considered the most  recently  killed
             by  a  later  yank  command. Repeating yank-pop will
             cycle through the killring any number of times.

  Lexical structure
     The shell splits input lines into words at blanks and  tabs.
     The special characters `&', `|', `;', `<', `>', `(', and `)'
     and the doubled characters `&&', `||',  `<<'  and  `>>'  are
     always separate words, whether or not they are surrounded by

     When the shell's input is not a terminal, the character  `#'
     is  taken  to begin a comment.  Each `#' and the rest of the
     input line on which it appears is discarded  before  further

     A  special  character (including a blank or tab) may be pre-
     vented from having its special meaning,  and  possibly  made
     part of another word, by preceding it with a backslash (`\')
     or enclosing it in single (`''), double  (`"')  or  backward
     (``')  quotes.  When not otherwise quoted a newline preceded
     by a `\' is equivalent to a blank, but  inside  quotes  this
     sequence results in a newline.

     Furthermore,  all  Substitutions  (see below) except History
     substitution can be prevented by enclosing the  strings  (or
     parts of strings) in which they appear with single quotes or
     by quoting the crucial character(s) (e.g., `$'  or  ``'  for
     Variable  substitution or Command substitution respectively)
     with `\'.  (Alias substitution is no exception:  quoting  in
     any  way any character of a word for which an alias has been
     defined prevents substitution of the alias.  The  usual  way
     of quoting an alias is to precede it with a backslash.) His-
     tory substitution is prevented by  backslashes  but  not  by
     single  quotes.   Strings  quoted  with  double  or backward
     quotes undergo Variable substitution and  Command  substitu-
     tion, but other substitutions are prevented.

     Text  inside  single  or double quotes becomes a single word
     (or part of one).  Metacharacters in these strings,  includ-
     ing  blanks  and  tabs, do not form separate words.  Only in
     one special case (see Command substitution below) can a dou-
     ble-quoted string yield parts of more than one word; single-
     quoted strings never do.  Backward quotes are special:  they
     signal Command substitution (q.v.), which may result in more
     than one word.

     Quoting complex strings, particularly  strings  which  them-
     selves contain quoting characters, can be confusing.  Remem-
     ber that quotes need not be used as they are in human  writ-
     ing!   It  may  be easier to quote not an entire string, but

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     only those parts of the string  which  need  quoting,  using
     different types of quoting to do so if appropriate.

     The backslash_quote shell variable (q.v.) can be set to make
     backslashes always quote `\', `'', and `"'.   (+)  This  may
     make  complex  quoting tasks easier, but it can cause syntax
     errors in csh(1) scripts.

     We now describe the various transformations the  shell  per-
     forms  on  the  input  in the order in which they occur.  We
     note in passing the data structures involved  and  the  com-
     mands  and  variables which affect them.  Remember that sub-
     stitutions can be prevented by quoting  as  described  under
     Lexical structure.

  History substitution
     Each command, or ``event'', input from the terminal is saved
     in the history list.  The previous command is always  saved,
     and  the  history  shell  variable can be set to a number to
     save that many commands.  The histdup shell variable can  be
     set  to  not  save duplicate events or consecutive duplicate

     Saved commands are numbered sequentially from 1 and  stamped
     with  the  time.   It  is not usually necessary to use event
     numbers, but the current event number can be  made  part  of
     the prompt by placing an `!' in the prompt shell variable.

     The  shell  actually  saves  history in expanded and literal
     (unexpanded) forms.  If the histlit shell variable  is  set,
     commands  that  display  and  store  history use the literal

     The history builtin command can  print,  store  in  a  file,
     restore  and  clear  the  history  list at any time, and the
     savehist and histfile shell variables can be  set  to  store
     the  history  list automatically on logout and restore it on

     History substitutions introduce words from the history  list
     into  the  input  stream, making it easy to repeat commands,
     repeat arguments of a previous command in the  current  com-
     mand,  or fix spelling mistakes in the previous command with
     little typing and a high degree of confidence.

     History substitutions begin with the  character  `!'.   They
     may  begin  anywhere  in  the  input stream, but they do not
     nest.  The `!' may be preceded by a `\' to prevent its  spe-
     cial  meaning;  for  convenience,  a `!' is passed unchanged
     when it is followed by a blank, tab, newline,  `='  or  `('.
     History  substitutions  also occur when an input line begins

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User Commands                                             TCSH(1)

     with `^'.   This  special  abbreviation  will  be  described
     later.   The  characters used to signal history substitution
     (`!' and `^') can be changed by setting the histchars  shell
     variable.  Any input line which contains a history substitu-
     tion is printed before it is executed.

     A history substitution may have an ``event  specification'',
     which  indicates the event from which words are to be taken,
     a ``word designator'', which selects particular  words  from
     the  chosen  event, and/or a ``modifier'', which manipulates
     the selected words.

     An event specification can be

         n       A number, referring to a particular event
         -n      An offset, referring to the event n  before  the
                 current event
         #       The  current  event.   This should be used care-
                 fully in csh(1), where there  is  no  check  for
                 recursion.   tcsh allows 10 levels of recursion.
         !       The previous event (equivalent to `-1')
         s       The most recent event whose  first  word  begins
                 with the string s
         ?s?     The  most recent event which contains the string
                 s.  The second `?' can be omitted if it is imme-
                 diately followed by a newline.

     For example, consider this bit of someone's history list:

          9  8:30    nroff -man
         10  8:31    cp
         11  8:36    vi
         12  8:37    diff

     The  commands  are  shown  with their event numbers and time
     stamps.  The current event, which we haven't typed  in  yet,
     is  event  13.   `!11'  and  `!-2'  refer to event 11.  `!!'
     refers to the previous event, 12.  `!!' can  be  abbreviated
     `!' if it is followed by `:' (`:' is described below).  `!n'
     refers to event 9, which begins  with  `n'.   `!?old?'  also
     refers to event 12, which contains `old'.  Without word des-
     ignators or modifiers history references  simply  expand  to
     the  entire  event,  so we might type `!cp' to redo the copy
     command or `!!|more' if the `diff' output scrolled  off  the
     top of the screen.

     History  references  may  be  insulated from the surrounding
     text with braces if necessary.  For example,  `!vdoc'  would
     look for a command beginning with `vdoc', and, in this exam-
     ple, not find one, but `!{v}doc' would expand  unambiguously
     to    `vi   wumpus.mandoc'.    Even   in   braces,   history

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     substitutions do not nest.

     (+) While csh(1) expands, for example, `!3d' to event 3 with
     the  letter  `d' appended to it, tcsh expands it to the last
     event beginning with `3d'; only completely numeric arguments
     are  treated  as  event  numbers.  This makes it possible to
     recall events beginning with numbers.  To expand `!3d' as in
     csh(1) say `!{3}d'.

     To select words from an event we can follow the event speci-
     fication by a `:' and a designator for  the  desired  words.
     The  words  of  an input line are numbered from 0, the first
     (usually command) word being 0, the second word (first argu-
     ment) being 1, etc.  The basic word designators are:

         0       The first (command) word
         n       The nth argument
         ^       The first argument, equivalent to `1'
         $       The last argument
         %       The word matched by an ?s? search
         x-y     A range of words
         -y      Equivalent to `0-y'
         *       Equivalent  to `^-$', but returns nothing if the
                 event contains only 1 word
         x*      Equivalent to `x-$'
         x-      Equivalent to `x*', but omitting the  last  word

     Selected  words are inserted into the command line separated
     by single blanks.  For example, the `diff'  command  in  the
     previous  example  might  have  been typed as `diff !!:1.old
     !!:1' (using `:1' to select the first argument from the pre-
     vious  event)  or  `diff !-2:2 !-2:1' to select and swap the
     arguments from the `cp' command.  If we  didn't  care  about
     the order of the `diff' we might have said `diff !-2:1-2' or
     simply `diff !-2:*'.  The `cp' command might have been writ-
     ten `cp !#:1.old', using `#' to refer to the cur-
     rent event.  `!n:-' would  reuse  the  first  two
     words   from   the   `nroff'  command  to  say  `nroff  -man'.

     The `:' separating the event  specification  from  the  word
     designator  can  be  omitted if the argument selector begins
     with a `^', `$', `*', `%' or `-'.  For example,  our  `diff'
     command might have been `diff !!^.old !!^' or, equivalently,
     `diff !!$.old !!$'.  However, if `!!' is abbreviated `!', an
     argument  selector beginning with `-' will be interpreted as
     an event specification.

     A history reference may have a word designator but no  event
     specification.   It  then  references  the previous command.
     Continuing our `diff' example, we  could  have  said  simply

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User Commands                                             TCSH(1)

     `diff  !^.old  !^'  or, to get the arguments in the opposite
     order, just `diff !*'.

     The word or words in a history reference can be  edited,  or
     ``modified'',  by  following  it with one or more modifiers,
     each preceded by a `:':

         h       Remove a trailing  pathname  component,  leaving
                 the head.
         t       Remove  all leading pathname components, leaving
                 the tail.
         r       Remove a filename extension `.xxx', leaving  the
                 root name.
         e       Remove all but the extension.
         u       Uppercase the first lowercase letter.
         l       Lowercase the first uppercase letter.
         s/l/r/  Substitute  l  for r.  l is simply a string like
                 r, not a regular expression as in the  eponymous
                 ed(1) command.  Any character may be used as the
                 delimiter in place of `/'; a `\' can be used  to
                 quote the delimiter inside l and r.  The charac-
                 ter `&' in the r is  replaced  by  l;  `\'  also
                 quotes  `&'.  If l is empty (``''), the l from a
                 previous substitution or the s from  a  previous
                 search or event number in event specification is
                 used.  The trailing delimiter may be omitted  if
                 it is immediately followed by a newline.
         &       Repeat the previous substitution.
         g       Apply  the following modifier once to each word.
         a (+)   Apply the following modifier as  many  times  as
                 possible  to  a single word.  `a' and `g' can be
                 used together  to  apply  a  modifier  globally.
                 With  the  `s'  modifier, only the patterns con-
                 tained in the original word are substituted, not
                 patterns that contain any substitution result.
         p       Print  the  new  command line but do not execute
         q       Quote the substituted words, preventing  further
         x       Like q, but break into words at blanks, tabs and

     Modifiers are applied to  only  the  first  modifiable  word
     (unless `g' is used).  It is an error for no word to be mod-

     For example, the `diff' command might have been  written  as
     `diff  !#^:r',  using  `:r' to remove `.old'
     from the first argument on the same line (`!#^').  We  could
     say  `echo  hello out there', then `echo !*:u' to capitalize
     `hello', `echo !*:au' to say it out loud, or  `echo  !*:agu'
     to  really  shout.   We  might  follow `mail -s "I forgot my

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User Commands                                             TCSH(1)

     password" rot' with `!:s/rot/root' to correct  the  spelling
     of  `root'  (but  see  Spelling  correction  for a different

     There is a special  abbreviation  for  substitutions.   `^',
     when  it is the first character on an input line, is equiva-
     lent to `!:s^'.  Thus we might have said `^rot^root' to make
     the  spelling  correction  in the previous example.  This is
     the only history  substitution  which  does  not  explicitly
     begin with `!'.

     (+) In csh as such, only one modifier may be applied to each
     history or variable expansion.  In tcsh, more than  one  may
     be used, for example

         % mv /usr/man/man1/wumpus.1
         % man !$:t:r
         man wumpus

     In  csh,  the  result would be `wumpus.1:r'.  A substitution
     followed by a colon may need to be insulated  from  it  with

         > mv a.out /usr/games/wumpus
         > setenv PATH !$:h:$PATH
         Bad ! modifier: $.
         > setenv PATH !{-2$:h}:$PATH
         setenv PATH /usr/games:/bin:/usr/bin:.

     The  first  attempt  would succeed in csh but fails in tcsh,
     because tcsh expects another modifier after the second colon
     rather than `$'.

     Finally,  history can be accessed through the editor as well
     as through the substitutions just described.   The  up-  and
     down-history,   history-search-backward   and  -forward,  i-
     search-back and -fwd, vi-search-back  and  -fwd,  copy-prev-
     word  and insert-last-word editor commands search for events
     in the history list and copy them  into  the  input  buffer.
     The  toggle-literal-history  editor command switches between
     the expanded and literal forms of history lines in the input
     buffer.   expand-history and expand-line expand history sub-
     stitutions in the current  word  and  in  the  entire  input
     buffer respectively.

  Alias substitution
     The  shell  maintains  a  list  of aliases which can be set,
     unset and printed by the alias and unalias commands.   After
     a command line is parsed into simple commands (see Commands)
     the first word of each command, left-to-right, is checked to
     see  if  it has an alias.  If so, the first word is replaced
     by the alias.  If the alias contains a history reference, it

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User Commands                                             TCSH(1)

     undergoes History substitution (q.v.) as though the original
     command were the previous input line.  If the alias does not
     contain  a  history  reference,  the  argument  list is left

     Thus if the alias for `ls' were  `ls  -l'  the  command  `ls
     /usr'  would  become  `ls  -l  /usr', the argument list here
     being undisturbed.  If the alias for `lookup' were `grep  !^
     /etc/passwd'  then  `lookup  bill'  would  become `grep bill
     /etc/passwd'.  Aliases can be used to introduce parser meta-
     syntax.  For example, `alias print 'pr \!* | lpr'' defines a
     ``command'' (`print') which pr(1)s its arguments to the line

     Alias  substitution  is repeated until the first word of the
     command has no alias.  If an  alias  substitution  does  not
     change  the  first  word  (as in the previous example) it is
     flagged to prevent a loop.  Other  loops  are  detected  and
     cause an error.

     Some  aliases  are  referred  to  by  the shell; see Special

  Variable substitution
     The shell maintains a list of variables, each of  which  has
     as  value a list of zero or more words.  The values of shell
     variables can be displayed and  changed  with  the  set  and
     unset  commands.   The  system  maintains  its  own  list of
     ``environment''  variables.   These  can  be  displayed  and
     changed with printenv, setenv and unsetenv.

     (+)  Variables  may  be made read-only with `set -r' (q.v.).
     Read-only variables may not be modified or unset; attempting
     to  do so will cause an error.  Once made read-only, a vari-
     able cannot be made writable, so `set  -r'  should  be  used
     with  caution.   Environment  variables cannot be made read-

     Some variables are set by the shell or referred  to  by  it.
     For  instance,  the argv variable is an image of the shell's
     argument list,  and  words  of  this  variable's  value  are
     referred to in special ways.  Some of the variables referred
     to by the shell are toggles; the shell does  not  care  what
     their  value  is,  only  whether  they  are set or not.  For
     instance, the verbose variable is a toggle which causes com-
     mand  input  to  be echoed.  The -v command line option sets
     this variable.  Special shell variables lists all  variables
     which are referred to by the shell.

     Other  operations treat variables numerically.  The `@' com-
     mand permits numeric calculations to be  performed  and  the
     result   assigned  to  a  variable.   Variable  values  are,

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User Commands                                             TCSH(1)

     however, always represented as (zero or more) strings.   For
     the  purposes of numeric operations, the null string is con-
     sidered to be zero, and the second and subsequent  words  of
     multi-word values are ignored.

     After  the input line is aliased and parsed, and before each
     command is  executed,  variable  substitution  is  performed
     keyed by `$' characters.  This expansion can be prevented by
     preceding the `$' with a `\' except  within  `"'s  where  it
     always  occurs,  and  within  `''s  where  it  never occurs.
     Strings quoted by ``' are  interpreted  later  (see  Command
     substitution below) so `$' substitution does not occur there
     until later, if at all.  A `$' is passed unchanged  if  fol-
     lowed by a blank, tab, or end-of-line.

     Input/output  redirections  are  recognized  before variable
     expansion, and are variable expanded separately.  Otherwise,
     the  command  name  and  entire  argument  list are expanded
     together.  It is thus possible for the first (command)  word
     (to this point) to generate more than one word, the first of
     which becomes the command name, and the rest of which become

     Unless  enclosed  in  `"'  or  given  the  `:q' modifier the
     results of variable substitution may eventually  be  command
     and  filename  substituted.   Within  `"',  a variable whose
     value consists of multiple words expands to a (portion of a)
     single  word,  with  the words of the variable's value sepa-
     rated by blanks.  When the `:q' modifier  is  applied  to  a
     substitution the variable will expand to multiple words with
     each word separated by a blank and quoted to  prevent  later
     command or filename substitution.

     The  following  metasequences  are  provided for introducing
     variable values into the shell input.  Except as  noted,  it
     is an error to reference a variable which is not set.

     ${name} Substitutes the words of the value of variable name,
             each separated by a  blank.   Braces  insulate  name
             from  following  characters which would otherwise be
             part of it.  Shell variables have  names  consisting
             of  letters  and digits starting with a letter.  The
             underscore character is  considered  a  letter.   If
             name  is  not  a  shell  variable, but is set in the
             environment, then that value is returned  (but  some
             of  the other forms given below are not available in
             this case).
             Substitutes only the selected words from  the  value
             of   name.    The   selector  is  subjected  to  `$'

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User Commands                                             TCSH(1)

             substitution and may consist of a single  number  or
             two numbers separated by a `-'.  The first word of a
             variable's value is numbered `1'.  If the first num-
             ber  of  a  range is omitted it defaults to `1'.  If
             the last member of a range is omitted it defaults to
             `$#name'.   The  selector `*' selects all words.  It
             is not an error for a range to be empty if the  sec-
             ond argument is omitted or in range.
     $0      Substitutes  the name of the file from which command
             input is being read.  An error occurs if the name is
             not known.
             Equivalent to `$argv[number]'.
     $*      Equivalent   to  `$argv',  which  is  equivalent  to

     The `:'  modifiers  described  under  History  substitution,
     except  for `:p', can be applied to the substitutions above.
     More than one may be used.  (+)  Braces  may  be  needed  to
     insulate  a  variable substitution from a literal colon just
     as with History  substitution  (q.v.);  any  modifiers  must
     appear within the braces.

     The  following  substitutions  can  not be modified with `:'

             Substitutes the string `1' if name is set, `0' if it
             is not.
     $?0     Substitutes  `1'  if  the  current input filename is
             known, `0' if it is not.  Always `0' in  interactive
             Substitutes the number of words in name.
     $#      Equivalent to `$#argv'.  (+)
             Substitutes the number of characters in name.  (+)
             Substitutes  the  number of characters in $argv[num-
             ber].  (+)
     $?      Equivalent to `$status'.  (+)
     $$      Substitutes the  (decimal)  process  number  of  the
             (parent) shell.
     $!      Substitutes the (decimal) process number of the last
             background process started by this shell.  (+)
     $_      Substitutes the command line  of  the  last  command
             executed.  (+)

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User Commands                                             TCSH(1)

     $<      Substitutes  a line from the standard input, with no
             further interpretation thereafter.  It can  be  used
             to  read  from  the keyboard in a shell script.  (+)
             While csh always quotes $<, as if it were equivalent
             to `$<:q', tcsh does not.  Furthermore, when tcsh is
             waiting for a line to be typed the user may type  an
             interrupt  to  interrupt the sequence into which the
             line is to be substituted, but csh  does  not  allow

     The  editor  command  expand-variables,  normally  bound  to
     `^X-$', can be used to interactively expand individual vari-

  Command, filename and directory stack substitution
     The  remaining  substitutions are applied selectively to the
     arguments of builtin commands.  This means that portions  of
     expressions  which  are  not  evaluated are not subjected to
     these expansions.  For commands which are  not  internal  to
     the  shell,  the command name is substituted separately from
     the argument list.  This occurs very late, after  input-out-
     put  redirection  is  performed,  and in a child of the main

  Command substitution
     Command substitution is indicated by a command  enclosed  in
     ``'.  The output from such a command is broken into separate
     words at blanks, tabs and newlines, and null words are  dis-
     carded.   The output is variable and command substituted and
     put in place of the original string.

     Command substitutions  inside  double  quotes  (`"')  retain
     blanks  and tabs; only newlines force new words.  The single
     final newline does not force a new word in any case.  It  is
     thus  possible for a command substitution to yield only part
     of a word, even if the command outputs a complete line.

     By default, the shell since version 6.12 replaces  all  new-
     line  and  carriage return characters in the command by spa-
     ces.  If this is switched off by unsetting csubstnonl,  new-
     lines separate commands as usual.

  Filename substitution
     If  a  word  contains any of the characters `*', `?', `[' or
     `{' or begins with the character `~' it is a  candidate  for
     filename  substitution,  also  known  as ``globbing''.  This
     word is then regarded as a pattern  (``glob-pattern''),  and
     replaced  with  an  alphabetically sorted list of file names
     which match the pattern.

     In matching filenames, the character `.' at the beginning of
     a  filename  or  immediately following a `/', as well as the

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User Commands                                             TCSH(1)

     character `/' must  be  matched  explicitly  (unless  either
     globdot  or globstar or both are set(+)).  The character `*'
     matches any string of characters, including the null string.
     The   character  `?'  matches  any  single  character.   The
     sequence `[...]' matches any one of the characters enclosed.
     Within  `[...]',  a  pair  of  characters  separated  by `-'
     matches any character lexically between the two.

     (+) Some glob-patterns can be negated: The sequence `[^...]'
     matches any single character not specified by the characters
     and/or ranges of characters in the braces.

     An entire glob-pattern can also be negated with `^':

         > echo *
         bang crash crunch ouch
         > echo ^cr*
         bang ouch

     Glob-patterns which do not use `?', `*', or  `[]'  or  which
     use `{}' or `~' (below) are not negated correctly.

     The  metanotation  `a{b,c,d}e'  is  a shorthand for `abe ace
     ade'.       Left-to-right      order      is      preserved:
     `/usr/source/s1/{oldls,ls}.c'           expands           to
     `/usr/source/s1/oldls.c /usr/source/s1/ls.c'.   The  results
     of  matches are sorted separately at a low level to preserve
     this order: `../{memo,*box}' might expand to `../memo ../box
     ../mbox'.  (Note that `memo' was not sorted with the results
     of matching `*box'.)  It is not an error when this construct
     expands  to  files which do not exist, but it is possible to
     get an error from a command to which the  expanded  list  is
     passed.   This  construct  may be nested.  As a special case
     the words `{', `}' and `{}' are passed undisturbed.

     The character `~' at the beginning of a filename  refers  to
     home  directories.  Standing alone, i.e., `~', it expands to
     the invoker's home directory as reflected in  the  value  of
     the home shell variable.  When followed by a name consisting
     of letters, digits and `-' characters the shell searches for
     a  user with that name and substitutes their home directory;
     thus `~ken' might expand to `/usr/ken' and `~ken/chmach'  to
     `/usr/ken/chmach'.   If  the  character `~' is followed by a
     character other than a letter or `/'  or  appears  elsewhere
     than  at the beginning of a word, it is left undisturbed.  A
     command           like            `setenv            MANPATH
     /usr/man:/usr/local/man:~/lib/man'  does  not, therefore, do
     home directory substitution as one might hope.

     It is an error for a glob-pattern containing `*',  `?',  `['
     or  `~',  with  or  without  `^',  not  to  match any files.

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User Commands                                             TCSH(1)

     However, only one pattern in a list  of  glob-patterns  must
     match  a  file  (so  that, e.g., `rm *.a *.c *.o' would fail
     only if there were no files in the current directory  ending
     in `.a', `.c', or `.o'), and if the nonomatch shell variable
     is set a pattern (or list of patterns) which matches nothing
     is left unchanged rather than causing an error.

     The  globstar  shell  variable  can  be set to allow `**' or
     `***' as a file glob pattern  that  matches  any  string  of
     characters  including `/', recursively traversing any exist-
     ing sub-directories.  For example, `ls **.c' will  list  all
     the  .c  files  in  the  current directory tree.  If used by
     itself, it will match match  zero  or  more  sub-directories
     (e.g.  `ls  /usr/include/**/time.h' will list any file named
     `time.h'   in   the   /usr/include   directory   tree;   `ls
     /usr/include/**time.h'   will   match   any   file   in  the
     /usr/include directory tree  ending  in  `time.h';  and  `ls
     /usr/include/**time**.h'  will match any .h file with `time'
     either in a subdirectory name or in  the  filename  itself).
     To  prevent  problems  with recursion, the `**' glob-pattern
     will not descend into a symbolic link  containing  a  direc-
     tory.  To override this, use `***' (+)

     The  noglob  shell  variable  can be set to prevent filename
     substitution, and the expand-glob editor  command,  normally
     bound  to  `^X-*', can be used to interactively expand indi-
     vidual filename substitutions.

  Directory stack substitution (+)
     The directory stack is a list of directories, numbered  from
     zero,  used  by  the  pushd,  popd and dirs builtin commands
     (q.v.).  dirs can print, store in a file, restore and  clear
     the  directory stack at any time, and the savedirs and dirs-
     file shell variables can be set to store the directory stack
     automatically  on  logout  and  restore  it  on  login.  The
     dirstack shell variable can be examined to see the directory
     stack  and  set to put arbitrary directories into the direc-
     tory stack.

     The character `=' followed by one or more digits expands  to
     an  entry  in  the  directory  stack.  The special case `=-'
     expands to the last directory in the stack.  For example,

         > dirs -v
         0       /usr/bin
         1       /usr/spool/uucp
         2       /usr/accts/sys
         > echo =1
         > echo =0/calendar
         > echo =-

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User Commands                                             TCSH(1)


     The noglob and nonomatch shell variables and the expand-glob
     editor  command apply to directory stack as well as filename

  Other substitutions (+)
     There are several more transformations involving  filenames,
     not  strictly  related  to  the above but mentioned here for
     completeness.  Any filename may be expanded to a  full  path
     when the symlinks variable (q.v.) is set to `expand'.  Quot-
     ing prevents this expansion, and the  normalize-path  editor
     command  does  it  on  demand.  The normalize-command editor
     command expands commands in PATH into full paths on  demand.
     Finally,  cd  and  pushd  interpret  `-'  as the old working
     directory (equivalent to the shell variable owd).   This  is
     not a substitution at all, but an abbreviation recognized by
     only those commands.  Nonetheless, it too can  be  prevented
     by quoting.

     The next three sections describe how the shell executes com-
     mands and deals with their input and output.

  Simple commands, pipelines and sequences
     A simple command is a sequence of words, the first of  which
     specifies  the  command  to be executed.  A series of simple
     commands joined by `|' characters  forms  a  pipeline.   The
     output  of  each  command  in a pipeline is connected to the
     input of the next.

     Simple commands and pipelines may be joined  into  sequences
     with  `;',  and will be executed sequentially.  Commands and
     pipelines can also be joined into  sequences  with  `||'  or
     `&&',  indicating,  as in the C language, that the second is
     to be executed only if the first fails or  succeeds  respec-

     A  simple  command,  pipeline  or  sequence may be placed in
     parentheses, `()', to form a simple command,  which  may  in
     turn  be  a component of a pipeline or sequence.  A command,
     pipeline or sequence can be executed without waiting for  it
     to terminate by following it with an `&'.

  Builtin and non-builtin command execution
     Builtin commands are executed within the shell.  If any com-
     ponent of a pipeline except the last is a  builtin  command,
     the pipeline is executed in a subshell.

     Parenthesized commands are always executed in a subshell.

         (cd; pwd); pwd

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User Commands                                             TCSH(1)

     thus  prints  the home directory, leaving you where you were
     (printing this after the home directory), while

         cd; pwd

     leaves you in the home  directory.   Parenthesized  commands
     are most often used to prevent cd from affecting the current

     When a command to be executed is found not to be  a  builtin
     command  the  shell  attempts  to  execute  the  command via
     execve(2).  Each word in the variable path names a directory
     in  which the shell will look for the command.  If the shell
     is not given a -f option, the  shell  hashes  the  names  in
     these directories into an internal table so that it will try
     an execve(2) in only a directory where there is a  possibil-
     ity  that  the  command  resides there.  This greatly speeds
     command location when a  large  number  of  directories  are
     present  in  the  search path. This hashing mechanism is not

     1.  If hashing is turned explicitly off via unhash.

     2.  If the shell was given a -f argument.

     3.  For each directory component  of  path  which  does  not
         begin with a `/'.

     4.  If the command contains a `/'.

     In  the  above four cases the shell concatenates each compo-
     nent of the path vector with the given command name to  form
     a  path name of a file which it then attempts to execute it.
     If execution is successful, the search stops.

     If the file has execute permissions but is not an executable
     to  the system (i.e., it is neither an executable binary nor
     a script that specifies its interpreter), then it is assumed
     to  be  a  file containing shell commands and a new shell is
     spawned to read it.  The shell special alias may be  set  to
     specify an interpreter other than the shell itself.

     On  systems  which  do not understand the `#!' script inter-
     preter convention the shell may be compiled to  emulate  it;
     see the version shell variable.  If so, the shell checks the
     first line of the file to see if it is of the form `#!inter-
     preter  arg  ...'.   If  it is, the shell starts interpreter
     with the given args and feeds the file  to  it  on  standard

     The  standard  input and standard output of a command may be

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User Commands                                             TCSH(1)

     redirected with the following syntax:

     < name  Open file name (which is first variable, command and
             filename expanded) as the standard input.
     << word Read the shell input up to a line which is identical
             to word.  word is not subjected to  variable,  file-
             name or command substitution, and each input line is
             compared to word before any substitutions  are  done
             on  this  input line.  Unless a quoting `\', `"', `'
             or ``' appears in word variable and command  substi-
             tution is performed on the intervening lines, allow-
             ing `\' to quote `$', `\' and ``'.   Commands  which
             are  substituted have all blanks, tabs, and newlines
             preserved, except for the  final  newline  which  is
             dropped.   The resultant text is placed in an anony-
             mous temporary file which is given to the command as
             standard input.
     > name
     >! name
     >& name
     >&! name
             The  file  name  is used as standard output.  If the
             file does not exist then it is created; if the  file
             exists, it is truncated, its previous contents being

             If the shell variable noclobber  is  set,  then  the
             file  must  not exist or be a character special file
             (e.g.,  a  terminal  or  `/dev/null')  or  an  error
             results.   This helps prevent accidental destruction
             of files.  In this case the `!' forms can be used to
             suppress this check.

             The  forms involving `&' route the diagnostic output
             into the specified file as well as the standard out-
             put.   name is expanded in the same way as `<' input
             filenames are.
     >> name
     >>& name
     >>! name
     >>&! name
             Like `>', but appends output to the end of name.  If
             the  shell  variable noclobber is set, then it is an
             error for the file not to exist, unless one  of  the
             `!' forms is given.

     A  command  receives  the environment in which the shell was
     invoked as modified by the input-output parameters  and  the
     presence  of  the  command in a pipeline.  Thus, unlike some
     previous shells, commands run from a file of shell  commands
     have  no  access  to  the  text  of the commands by default;
     rather they receive  the  original  standard  input  of  the

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User Commands                                             TCSH(1)

     shell.   The `<<' mechanism should be used to present inline
     data.  This permits shell command  scripts  to  function  as
     components  of  pipelines and allows the shell to block read
     its input.  Note that the default standard input for a  com-
     mand  run  detached is not the empty file /dev/null, but the
     original standard input of the shell.  If this is a terminal
     and  if the process attempts to read from the terminal, then
     the process will block and the user will  be  notified  (see

     Diagnostic  output  may  be directed through a pipe with the
     standard output.  Simply use the form `|&' rather than  just

     The  shell cannot presently redirect diagnostic output with-
     out also redirecting standard output, but `(command  >  out-
     put-file)  >& error-file' is often an acceptable workaround.
     Either output-file or error-file may be `/dev/tty'  to  send
     output to the terminal.

     Having  described how the shell accepts, parses and executes
     command lines, we now turn to a variety of its  useful  fea-

  Control flow
     The shell contains a number of commands which can be used to
     regulate  the  flow  of  control  in  command  files  (shell
     scripts)  and  (in  limited  but  useful ways) from terminal
     input.  These commands all operate by forcing the  shell  to
     reread  or skip in its input and, due to the implementation,
     restrict the placement of some of the commands.

     The foreach, switch, and while statements, as  well  as  the
     if-then-else  form  of  the  if  statement, require that the
     major keywords appear in a single simple command on an input
     line as shown below.

     If  the  shell's input is not seekable, the shell buffers up
     input whenever a loop is being read and  performs  seeks  in
     this  internal buffer to accomplish the rereading implied by
     the loop.  (To the extent that this allows,  backward  gotos
     will succeed on non-seekable inputs.)

     The if, while and exit builtin commands use expressions with
     a common syntax.  The expressions can  include  any  of  the
     operators  described  in the next three sections.  Note that
     the @ builtin command (q.v.) has its own separate syntax.

  Logical, arithmetical and comparison operators
     These operators are similar to those of C and have the  same

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User Commands                                             TCSH(1)

     precedence.  They include

         ||  &&  |  ^  &  ==  !=  =~  !~  <=  >=
         <  > <<  >>  +  -  *  /  %  !  ~  (  )

     Here  the  precedence increases to the right, `==' `!=' `=~'
     and `!~', `<=' `>=' `<' and `>', `<<' and `>>', `+' and `-',
     `*'  `/'  and  `%' being, in groups, at the same level.  The
     `==' `!=' `=~' and `!~' operators compare their arguments as
     strings;  all others operate on numbers.  The operators `=~'
     and `!~' are like `!=' and `==' except that the  right  hand
     side  is  a glob-pattern (see Filename substitution) against
     which the left hand operand is matched.   This  reduces  the
     need  for use of the switch builtin command in shell scripts
     when all that is really needed is pattern matching.

     Null or missing arguments are considered `0'.   The  results
     of all expressions are strings, which represent decimal num-
     bers.  It is important to note that no two components of  an
     expression can appear in the same word; except when adjacent
     to components of expressions which are syntactically signif-
     icant to the parser (`&' `|' `<' `>' `(' `)') they should be
     surrounded by spaces.

  Command exit status
     Commands can be executed in expressions and their exit  sta-
     tus  returned  by enclosing them in braces (`{}').  Remember
     that the braces should be separated from the  words  of  the
     command  by  spaces.   Command executions succeed, returning
     true, i.e., `1', if the command exits with status 0,  other-
     wise  they  fail,  returning  false,  i.e.,  `0'.   If  more
     detailed status information is  required  then  the  command
     should  be  executed outside of an expression and the status
     shell variable examined.

  File inquiry operators
     Some of these operators perform true/false  tests  on  files
     and  related  objects.  They are of the form -op file, where
     op is one of

         r   Read access
         w   Write access
         x   Execute access
         X   Executable in the path or shell builtin,  e.g.,  `-X
             ls'  and  `-X  ls-F'  are  generally  true,  but `-X
             /bin/ls' is not (+)
         e   Existence
         o   Ownership
         z   Zero size
         s   Non-zero size (+)
         f   Plain file
         d   Directory

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User Commands                                             TCSH(1)

         l   Symbolic link (+) *
         b   Block special file (+)
         c   Character special file (+)
         p   Named pipe (fifo) (+) *
         S   Socket special file (+) *
         u   Set-user-ID bit is set (+)
         g   Set-group-ID bit is set (+)
         k   Sticky bit is set (+)
         t   file (which  must  be  a  digit)  is  an  open  file
             descriptor for a terminal device (+)
         R   Has been migrated (Convex only) (+)
         L   Applies  subsequent operators in a multiple-operator
             test to a symbolic link rather than to the  file  to
             which the link points (+) *

     file is command and filename expanded and then tested to see
     if it has the specified relationship to the real  user.   If
     file does not exist or is inaccessible or, for the operators
     indicated by `*', if the specified file type does not  exist
     on  the  current  system,  then  all enquiries return false,
     i.e., `0'.

     These operators may be combined for conciseness: `-xy  file'
     is  equivalent  to  `-x  file && -y file'.  (+) For example,
     `-fx' is true (returns `1') for plain executable files,  but
     not for directories.

     L  may  be  used in a multiple-operator test to apply subse-
     quent operators to a symbolic link rather than to  the  file
     to  which  the link points.  For example, `-lLo' is true for
     links owned by the invoking user.  Lr, Lw and Lx are  always
     true  for  links and false for non-links.  L has a different
     meaning when it is the last operator in a  multiple-operator
     test; see below.

     It  is possible but not useful, and sometimes misleading, to
     combine operators which expect file to be a file with opera-
     tors  which do not (e.g., X and t).  Following L with a non-
     file operator can lead to particularly strange results.

     Other operators return other information, i.e., not just `0'
     or  `1'.  (+) They have the same format as before; op may be
     one of

         A       Last file access time, as the number of  seconds
                 since the epoch
         A:      Like  A, but in timestamp format, e.g., `Fri May
                 14 16:36:10 1993'
         M       Last file modification time
         M:      Like M, but in timestamp format
         C       Last inode modification time
         C:      Like C, but in timestamp format

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User Commands                                             TCSH(1)

         D       Device number
         I       Inode number
         F       Composite   file   identifier,   in   the   form
         L       The  name  of  the file pointed to by a symbolic
         N       Number of (hard) links
         P       Permissions, in octal, without leading zero
         P:      Like P, with leading zero
         Pmode   Equivalent to `-P  file  &  mode',  e.g.,  `-P22
                 file'  returns `22' if file is writable by group
                 and other, `20' if by group only, and `0' if  by
         Pmode:  Like Pmode, with leading zero
         U       Numeric userid
         U:      Username,  or the numeric userid if the username
                 is unknown
         G       Numeric groupid
         G:      Groupname, or the numeric groupid if the  group-
                 name is unknown
         Z       Size, in bytes

     Only  one of these operators may appear in a multiple-opera-
     tor test, and it must be the last.  Note that L has  a  dif-
     ferent  meaning  at  the end of and elsewhere in a multiple-
     operator test.  Because `0' is a valid return value for many
     of  these  operators, they do not return `0' when they fail:
     most return `-1', and F returns `:'.

     If the shell is compiled with POSIX defined (see the version
     shell  variable),  the  result of a file inquiry is based on
     the permission bits of the file and not on the result of the
     access(2)  system  call.   For  example, if one tests a file
     with -w whose permissions would ordinarily allow writing but
     which  is  on a file system mounted read-only, the test will
     succeed in a POSIX shell but fail in a non-POSIX shell.

     File inquiry  operators  can  also  be  evaluated  with  the
     filetest builtin command (q.v.) (+).

     The  shell  associates a job with each pipeline.  It keeps a
     table of current jobs, printed  by  the  jobs  command,  and
     assigns  them  small integer numbers.  When a job is started
     asynchronously with `&', the shell prints a line which looks

         [1] 1234

     indicating that the job which was started asynchronously was
     job number 1 and had one (top-level) process, whose  process
     id was 1234.

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User Commands                                             TCSH(1)

     If  you  are running a job and wish to do something else you
     may hit the suspend key (usually `^Z'), which sends  a  STOP
     signal  to  the  current  job.  The shell will then normally
     indicate that the job has been `Suspended' and print another
     prompt.   If  the  listjobs  shell variable is set, all jobs
     will be listed like the jobs builtin command; if it  is  set
     to  `long'  the  listing  will be in long format, like `jobs
     -l'.  You can then manipulate the  state  of  the  suspended
     job.   You can put it in the ``background'' with the bg com-
     mand or run some other commands and eventually bring the job
     back into the ``foreground'' with fg.  (See also the run-fg-
     editor editor command.)  A `^Z' takes effect immediately and
     is like an interrupt in that pending output and unread input
     are discarded when it is typed.  The  wait  builtin  command
     causes  the  shell  to  wait for all background jobs to com-

     The `^]' key sends a delayed suspend signal, which does  not
     generate  a  STOP signal until a program attempts to read(2)
     it, to the current job.  This can usefully  be  typed  ahead
     when  you  have  prepared  some commands for a job which you
     wish to stop after it has read them.  The `^Y' key  performs
     this  function  in  csh(1); in tcsh, `^Y' is an editing com-
     mand.  (+)

     A job being run in the background stops if it tries to  read
     from  the terminal.  Background jobs are normally allowed to
     produce output, but this can be disabled by giving the  com-
     mand  `stty tostop'.  If you set this tty option, then back-
     ground jobs will stop when they try to produce  output  like
     they do when they try to read input.

     There  are  several ways to refer to jobs in the shell.  The
     character `%' introduces a job name.  If you wish  to  refer
     to job number 1, you can name it as `%1'.  Just naming a job
     brings it to the foreground; thus `%1' is a synonym for  `fg
     %1',  bringing  job  1 back into the foreground.  Similarly,
     saying `%1 &' resumes job 1 in the background, just like `bg
     %1'.   A  job  can also be named by an unambiguous prefix of
     the string typed  in  to  start  it:  `%ex'  would  normally
     restart  a  suspended ex(1) job, if there were only one sus-
     pended job whose name began with the  string  `ex'.   It  is
     also  possible to say `%?string' to specify a job whose text
     contains string, if there is only one such job.

     The shell maintains a notion of  the  current  and  previous
     jobs.   In  output  pertaining  to  jobs, the current job is
     marked with a `+' and the previous  job  with  a  `-'.   The
     abbreviations  `%+', `%', and (by analogy with the syntax of
     the history mechanism) `%%' all refer to  the  current  job,
     and `%-' refers to the previous job.

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User Commands                                             TCSH(1)

     The  job  control mechanism requires that the stty(1) option
     `new' be set on some systems.  It  is  an  artifact  from  a
     `new'  implementation of the tty driver which allows genera-
     tion of interrupt characters from the keyboard to tell  jobs
     to  stop.   See  stty(1)  and  the setty builtin command for
     details on setting options in the new tty driver.

  Status reporting
     The shell learns  immediately  whenever  a  process  changes
     state.   It  normally  informs  you  whenever  a job becomes
     blocked so that no further progress is  possible,  but  only
     right  before  it  prints a prompt.  This is done so that it
     does not otherwise disturb your work.  If, however, you  set
     the shell variable notify, the shell will notify you immedi-
     ately of changes of status in  background  jobs.   There  is
     also  a shell command notify which marks a single process so
     that its status changes will be  immediately  reported.   By
     default   notify  marks  the  current  process;  simply  say
     `notify' after starting a background job to mark it.

     When you try to leave the shell while jobs are stopped,  you
     will  be warned that `There are suspended jobs.' You may use
     the jobs command to see what they are.  If you  do  this  or
     immediately try to exit again, the shell will not warn you a
     second time, and the suspended jobs will be terminated.

  Automatic, periodic and timed events (+)
     There are various  ways  to  run  commands  and  take  other
     actions automatically at various times in the ``life cycle''
     of the shell.  They are summarized here,  and  described  in
     detail under the appropriate Builtin commands, Special shell
     variables and Special aliases.

     The sched builtin command puts commands in a scheduled-event
     list, to be executed by the shell at a given time.

     The  beepcmd,  cwdcmd, periodic, precmd, postcmd, and jobcmd
     Special aliases can be set, respectively,  to  execute  com-
     mands  when the shell wants to ring the bell, when the work-
     ing directory changes, every tperiod  minutes,  before  each
     prompt,  before  each command gets executed, after each com-
     mand gets executed, and when a job is started or is  brought
     into the foreground.

     The  autologout shell variable can be set to log out or lock
     the shell after a given number of minutes of inactivity.

     The mail shell variable can be set to  check  for  new  mail

     The  printexitvalue  shell  variable can be set to print the
     exit status of commands which exit with a status other  than

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User Commands                                             TCSH(1)


     The  rmstar  shell variable can be set to ask the user, when
     `rm *' is typed, if that is really what was meant.

     The time shell variable can  be  set  to  execute  the  time
     builtin  command  after  the  completion of any process that
     takes more than a given number of CPU seconds.

     The watch and who shell variables can be set to report  when
     selected  users  log  in or out, and the log builtin command
     reports on those users at any time.

  Native Language System support (+)
     The shell is eight bit clean (if so compiled; see  the  ver-
     sion  shell variable) and thus supports character sets need-
     ing this  capability.   NLS  support  differs  depending  on
     whether  or  not  the shell was compiled to use the system's
     NLS (again, see version).  In either case,  7-bit  ASCII  is
     the  default  character  code  (e.g.,  the classification of
     which characters are printable) and  sorting,  and  changing
     the  LANG  or  LC_CTYPE environment variables causes a check
     for possible changes in these respects.

     When using the system's NLS, the setlocale(3C)  function  is
     called  to  determine appropriate character code/classifica-
     tion and sorting (e.g., a 'en_CA.UTF-8' would yield  "UTF-8"
     as  a character code).  This function typically examines the
     LANG and LC_CTYPE environment variables; refer to the system
     documentation  for further details.  When not using the sys-
     tem's NLS, the shell simulates it by assuming that  the  ISO
     8859-1 character set is used whenever either of the LANG and
     LC_CTYPE variables are  set,  regardless  of  their  values.
     Sorting is not affected for the simulated NLS.

     In addition, with both real and simulated NLS, all printable
     characters in the range \200-\377, i.e., those that have  M-
     char bindings, are automatically rebound to self-insert-com-
     mand.   The  corresponding  binding  for   the   escape-char
     sequence,  if  any, is left alone.  These characters are not
     rebound if the NOREBIND environment variable is  set.   This
     may  be useful for the simulated NLS or a primitive real NLS
     which assumes full ISO 8859-1.  Otherwise, all M-char  bind-
     ings in the range \240-\377 are effectively undone.  Explic-
     itly rebinding the relevant keys with bindkey is  of  course
     still possible.

     Unknown  characters  (i.e., those that are neither printable
     nor control characters) are printed in the format \nnn.   If
     the  tty  is  not  in 8 bit mode, other 8 bit characters are
     printed by converting them to ASCII and using standout mode.
     The  shell  never  changes  the  7/8 bit mode of the tty and

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User Commands                                             TCSH(1)

     tracks user-initiated changes of 7/8 bit  mode.   NLS  users
     (or,  for that matter, those who want to use a meta key) may
     need to explicitly set the tty in 8  bit  mode  through  the
     appropriate stty(1) command in, e.g., the ~/.login file.

  OS variant support (+)
     A  number  of  new  builtin commands are provided to support
     features in particular operating systems.  All are described
     in detail in the Builtin commands section.

     On  systems that support TCF (aix-ibm370, aix-ps2), getspath
     and setspath get and set the system execution path, getxvers
     and setxvers get and set the experimental version prefix and
     migrate migrates processes between sites.  The jobs  builtin
     prints the site on which each job is executing.

     Under  BS2000,  bs2cmd  executes  commands of the underlying
     BS2000/OSD operating system.

     Under Domain/OS, inlib adds shared libraries to the  current
     environment,  rootnode  changes the rootnode and ver changes
     the systype.

     Under Mach, setpath is equivalent to Mach's setpath(1).

     Under Masscomp/RTU and Harris CX/UX, universe sets the  uni-

     Under  Harris  CX/UX,  ucb  or  att runs a command under the
     specified universe.

     Under Convex/OS, warp prints or sets the universe.

     The VENDOR, OSTYPE and MACHTYPE environment variables  indi-
     cate  respectively  the vendor, operating system and machine
     type (microprocessor class or machine model) of  the  system
     on which the shell thinks it is running.  These are particu-
     larly useful when sharing one's home directory between  sev-
     eral types of machines; one can, for example,

         set path = (~/bin.$MACHTYPE /usr/ucb /bin /usr/bin .)

     in  one's  ~/.login  and  put  executables compiled for each
     machine in the appropriate directory.

     The version shell variable indicates what options were  cho-
     sen when the shell was compiled.

     Note  also  the  newgrp  builtin, the afsuser and echo_style
     shell variables and the system-dependent  locations  of  the
     shell's input files (see FILES).

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  Signal handling
     Login   shells  ignore  interrupts  when  reading  the  file
     ~/.logout.  The shell ignores quit  signals  unless  started
     with  -q.  Login shells catch the terminate signal, but non-
     login shells inherit the terminate behavior from their  par-
     ents.   Other signals have the values which the shell inher-
     ited from its parent.

     In shell scripts, the shell's handling of interrupt and ter-
     minate  signals  can be controlled with onintr, and its han-
     dling of hangups can be controlled with hup and nohup.

     The shell exits on a hangup (see also the logout shell vari-
     able).   By  default,  the  shell's children do too, but the
     shell does not send  them  a  hangup  when  it  exits.   hup
     arranges  for  the shell to send a hangup to a child when it
     exits, and nohup sets a child to ignore hangups.

  Terminal management (+)
     The shell uses three different sets  of  terminal  (``tty'')
     modes: `edit', used when editing, `quote', used when quoting
     literal characters, and `execute', used when executing  com-
     mands.  The shell holds some settings in each mode constant,
     so commands which leave the tty in a confused state  do  not
     interfere with the shell.  The shell also matches changes in
     the speed and padding of the tty.  The  list  of  tty  modes
     that are kept constant can be examined and modified with the
     setty builtin.  Note that although the  editor  uses  CBREAK
     mode  (or  its  equivalent), it takes typed-ahead characters

     The echotc, settc and telltc commands can be used to manipu-
     late  and debug terminal capabilities from the command line.

     On systems that support SIGWINCH  or  SIGWINDOW,  the  shell
     adapts  to  window  resizing  automatically  and adjusts the
     environment variables LINES and  COLUMNS  if  set.   If  the
     environment  variable  TERMCAP  contains li# and co# fields,
     the shell adjusts them to reflect the new window size.

     The next sections of this manual describe all of the  avail-
     able  Builtin  commands,  Special  aliases and Special shell

  Builtin commands
     %job    A synonym for the fg builtin command.

     %job &  A synonym for the bg builtin command.

     :       Does nothing, successfully.

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User Commands                                             TCSH(1)

     @ name = expr
     @ name[index] = expr
     @ name++|--
     @ name[index]++|--
             The first form prints the values of all shell  vari-

             The  second  form assigns the value of expr to name.
             The third form assigns the  value  of  expr  to  the
             index'th  component  of  name;  both  name  and  its
             index'th component must already exist.

             expr may contain the operators `*', `+', etc., as in
             C.   If  expr  contains  `<', `>', `&' or `' then at
             least that part of expr must be placed within  `()'.
             Note  that the syntax of expr has nothing to do with
             that described under Expressions.

             The fourth  and  fifth  forms  increment  (`++')  or
             decrement (`--') name or its index'th component.

             The  space  between  `@'  and name is required.  The
             spaces between name and `=' and between `=' and expr
             are  optional.  Components of expr must be separated
             by spaces.

     alias [name [wordlist]]
             Without arguments, prints all aliases.   With  name,
             prints  the alias for name.  With name and wordlist,
             assigns wordlist as the alias of name.  wordlist  is
             command  and  filename substituted.  name may not be
             `alias' or `unalias'.  See also the unalias  builtin

     alloc   Shows  the amount of dynamic memory acquired, broken
             down into used and free memory.   With  an  argument
             shows  the  number  of  free and used blocks in each
             size category.  The categories start at size  8  and
             double at each step.  This command's output may vary
             across system types, because systems other than  the
             VAX may use a different memory allocator.

     bg [%job ...]
             Puts  the specified jobs (or, without arguments, the
             current job) into the background, continuing each if
             it  is  stopped.  job may be a number, a string, `',
             `%', `+' or `-' as described under Jobs.

     bindkey [-l|-d|-e|-v|-u] (+)
     bindkey [-a] [-b] [-k] [-r] [--] key (+)
     bindkey [-a] [-b] [-k] [-c|-s] [--] key command (+)

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User Commands                                             TCSH(1)

             Without options, the first form lists all bound keys
             and  the  editor command to which each is bound, the
             second form lists the editor command to which key is
             bound  and  the  third form binds the editor command
             command to key.  Options include:

             -l  Lists all editor commands and a  short  descrip-
                 tion of each.
             -d  Binds  all keys to the standard bindings for the
                 default editor.
             -e  Binds all keys to the  standard  GNU  Emacs-like
             -v  Binds  all keys to the standard vi(1)-like bind-
             -a  Lists or changes key-bindings in the alternative
                 key map.  This is the key map used in vi command
             -b  key is interpreted as a control character  writ-
                 ten   ^character  (e.g.,  `^A')  or  C-character
                 (e.g., `C-A'), a meta character written  M-char-
                 acter  (e.g.,  `M-A'), a function key written F-
                 string (e.g., `F-string'), or an extended prefix
                 key written X-character (e.g., `X-A').
             -k  key is interpreted as a symbolic arrow key name,
                 which may be one  of  `down',  `up',  `left'  or
             -r  Removes key's binding.  Be careful: `bindkey -r'
                 does not bind key to self-insert-command (q.v.),
                 it unbinds key completely.
             -c  command  is interpreted as a builtin or external
                 command instead of an editor command.
             -s  command is taken as a literal string and treated
                 as terminal input when key is typed.  Bound keys
                 in command  are  themselves  reinterpreted,  and
                 this continues for ten levels of interpretation.
             --  Forces a break from option  processing,  so  the
                 next word is taken as key even if it begins with
             -u (or any invalid option)
                 Prints a usage message.

             key may be a single character or  a  string.   If  a
             command is bound to a string, the first character of
             the string is  bound  to  sequence-lead-in  and  the
             entire string is bound to the command.

             Control  characters  in key can be literal (they can
             be typed by preceding them with the  editor  command
             quoted-insert,  normally  bound  to `^V') or written
             caret-character style, e.g., `^A'.  Delete is  writ-
             ten  `^?'   (caret-question  mark).  key and command
             can contain backslashed  escape  sequences  (in  the

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User Commands                                             TCSH(1)

             style of System V echo(1)) as follows:

                 \a      Bell
                 \b      Backspace
                 \e      Escape
                 \f      Form feed
                 \n      Newline
                 \r      Carriage return
                 \t      Horizontal tab
                 \v      Vertical tab
                 \nnn    The ASCII character corresponding to the
                         octal number nnn

             `\' nullifies the special meaning of  the  following
             character, if it has any, notably `\' and `^'.

     bs2cmd bs2000-command (+)
             Passes  bs2000-command  to the BS2000 command inter-
             preter for execution. Only non-interactive  commands
             can  be  executed, and it is not possible to execute
             any command that would overlay the image of the cur-
             rent  process,  like  /EXECUTE  or  /CALL-PROCEDURE.
             (BS2000 only)

     break   Causes execution to resume  after  the  end  of  the
             nearest  enclosing  foreach or while.  The remaining
             commands on the current line are  executed.   Multi-
             level  breaks  are thus possible by writing them all
             on one line.

     breaksw Causes a break from a  switch,  resuming  after  the

     builtins (+)
             Prints the names of all builtin commands.

     bye (+) A synonym for the logout builtin command.  Available
             only if the shell was so compiled; see  the  version
             shell variable.

     case label:
             A label in a switch statement as discussed below.

     cd [-p] [-l] [-n|-v] [I--] [name]
             If  a  directory  name is given, changes the shell's
             working directory to name.  If not, changes to home.
             If  name  is  `-'  it is interpreted as the previous
             working directory (see Other substitutions).  (+) If
             name  is not a subdirectory of the current directory
             (and does not begin with `/', `./' or  `../'),  each
             component  of  the variable cdpath is checked to see
             if it has a subdirectory name.  Finally, if all else

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User Commands                                             TCSH(1)

             fails  but  name  is  a  shell  variable whose value
             begins with `/', then this is tried to see if it  is
             a directory.

             With -p, prints the final directory stack, just like
             dirs.  The -l, -n and -v flags have the same  effect
             on  cd  as on dirs, and they imply -p.  (+) Using --
             forces a break from option processing  so  the  next
             word  is  taken  as  the  directory  name even if it
             begins with '-'. (+)

             See also the implicitcd shell variable.

     chdir   A synonym for the cd builtin command.

     complete [command  [word/pattern/list[:select]/[[suffix]/]
             Without arguments, lists all completions.  With com-
             mand,  lists  completions for command.  With command
             and word etc., defines completions.

             command may be a full command name or a glob-pattern
             (see  Filename substitution).  It can begin with `-'
             to indicate that completion should be used only when
             command is ambiguous.

             word  specifies  which  word relative to the current
             word is to be completed, and may be one of the  fol-

                 c   Current-word completion.  pattern is a glob-
                     pattern which must match  the  beginning  of
                     the  current word on the command line.  pat-
                     tern is ignored when completing the  current
                 C   Like c, but includes pattern when completing
                     the current word.
                 n   Next-word completion.  pattern  is  a  glob-
                     pattern  which  must  match the beginning of
                     the previous word on the command line.
                 N   Like n, but must match the beginning of  the
                     word two before the current word.
                 p   Position-dependent completion.  pattern is a
                     numeric range, with the same syntax used  to
                     index  shell  variables,  which must include
                     the current word.

             list, the list of possible completions, may  be  one
             of the following:

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User Commands                                             TCSH(1)

                 a       Aliases
                 b       Bindings (editor commands)
                 c       Commands (builtin or external commands)
                 C       External  commands  which begin with the
                         supplied path prefix
                 d       Directories
                 D       Directories which begin  with  the  sup-
                         plied path prefix
                 e       Environment variables
                 f       Filenames
                 F       Filenames  which begin with the supplied
                         path prefix
                 g       Groupnames
                 j       Jobs
                 l       Limits
                 n       Nothing
                 s       Shell variables
                 S       Signals
                 t       Plain (``text'') files
                 T       Plain (``text'') files which begin  with
                         the supplied path prefix
                 v       Any variables
                 u       Usernames
                 x       Like  n,  but  prints  select when list-
                         choices is used.
                 X       Completions
                 $var    Words from the variable var
                 (...)   Words from the given list
                 `...`   Words from the output of command

             select is an optional glob-pattern.  If given, words
             from  only list that match select are considered and
             the fignore shell variable  is  ignored.   The  last
             three types of completion may not have a select pat-
             tern, and x uses select as  an  explanatory  message
             when the list-choices editor command is used.

             suffix  is  a  single  character to be appended to a
             successful completion.  If  null,  no  character  is
             appended.   If  omitted  (in  which  case the fourth
             delimiter can also be omitted), a slash is  appended
             to directories and a space to other words.

             command  invoked  from  `...` version has additional
             environment  variable  set,  the  variable  name  is
             COMMAND_LINE  and  contains  (as its name indicates)
             contents of the current (already typed  in)  command
             line.  One  can  examine  and  use  contents  of the
             COMMAND_LINE variable in her custom script to  build
             more  sophisticated  completions (see completion for
             svn(1) included in this package).

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User Commands                                             TCSH(1)

             Now for some  examples.   Some  commands  take  only
             directories  as  arguments, so there's no point com-
             pleting plain files.

                 > complete cd 'p/1/d/'

             completes only the first word following `cd' (`p/1')
             with  a  directory.   p-type  completion can also be
             used to narrow down command completion:

                 > co[^D]
                 complete compress
                 > complete -co* 'p/0/(compress)/'
                 > co[^D]
                 > compress

             This completion completes commands (words  in  posi-
             tion  0, `p/0') which begin with `co' (thus matching
             `co*') to `compress' (the only word  in  the  list).
             The leading `-' indicates that this completion is to
             be used with only ambiguous commands.

                 > complete find 'n/-user/u/'

             is an example of n-type completion.  Any  word  fol-
             lowing  `find'  and immediately following `-user' is
             completed from the list of users.

                 > complete cc 'c/-I/d/'

             demonstrates c-type completion.  Any word  following
             `cc'  and  beginning  with  `-I'  is  completed as a
             directory.  `-I' is not taken as part of the  direc-
             tory because we used lowercase c.

             Different  lists are useful with different commands.

                 > complete alias 'p/1/a/'
                 > complete man 'p/*/c/'
                 > complete set 'p/1/s/'
                 > complete true 'p/1/x:Truth has no options./'

             These complete words following `alias' with aliases,
             `man' with commands, and `set' with shell variables.
             `true' doesn't have any options, so x  does  nothing
             when  completion  is attempted and prints `Truth has
             no options.' when completion choices are listed.

             Note that the man example, and several  other  exam-
             ples  below,  could  just as well have used 'c/*' or
             'n/*' as 'p/*'.

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User Commands                                             TCSH(1)

             Words can be completed from a variable evaluated  at
             completion time,

                 > complete ftp 'p/1/$hostnames/'
                 >  set  hostnames  = (
                 > ftp [^D]
                 > ftp [^C]
                 > set hostnames  =  (
                 > ftp [^D]

             or from a command run at completion time:

                 > complete kill 'p/*/`ps | awk \{print\ \$1\}`/'
                 > kill -9 [^D]
                 23113 23377 23380 23406 23429 23529 23530 PID

             Note that the complete command does not itself quote
             its  arguments,  so  the  braces,  space  and `$' in
             `{print $1}' must be quoted explicitly.

             One command can have multiple completions:

                 > complete dbx 'p/2/(core)/' 'p/*/c/'

             completes the second argument to `dbx' with the word
             `core'  and all other arguments with commands.  Note
             that the positional completion is  specified  before
             the  next-word  completion.  Because completions are
             evaluated from left to right, if the next-word  com-
             pletion  were  specified first it would always match
             and the positional completion would  never  be  exe-
             cuted.   This  is  a  common mistake when defining a

             The select pattern is useful when  a  command  takes
             files  with only particular forms as arguments.  For

                 > complete cc 'p/*/f:*.[cao]/'

             completes `cc' arguments to  files  ending  in  only
             `.c', `.a', or `.o'.  select can also exclude files,
             using negation of a glob-pattern as described  under
             Filename substitution.  One might use

                 >                   complete                  rm

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User Commands                                             TCSH(1)

             to exclude precious source code  from  `rm'  comple-
             tion.   Of  course,  one  could  still type excluded
             names manually or override the completion  mechanism
             using the complete-word-raw or list-choices-raw edi-
             tor commands (q.v.).

             The `C', `D', `F' and `T' lists are like  `c',  `d',
             `f'  and  `t'  respectively, but they use the select
             argument in a different way: to restrict  completion
             to  files  beginning  with a particular path prefix.
             For example, the Elm mail program  uses  `='  as  an
             abbreviation  for  one's  mail directory.  One might

                 > complete elm c@=@F:$HOME/Mail/@

             to complete `elm  -f  ='  as  if  it  were  `elm  -f
             ~/Mail/'.   Note  that we used `@' instead of `/' to
             avoid confusion with the  select  argument,  and  we
             used  `$HOME'  instead of `~' because home directory
             substitution works at only the beginning of a  word.

             suffix  is  used  to  add  a nonstandard suffix (not
             space or `/' for directories) to completed words.

                 > complete finger 'c/*@/$hostnames/' 'p/1/u/@'

             completes arguments to `finger'  from  the  list  of
             users,  appends an `@', and then completes after the
             `@' from the `hostnames' variable.  Note  again  the
             order in which the completions are specified.

             Finally, here's a complex example for inspiration:

                 > complete find \
                 'n/-name/f/' 'n/-newer/f/' 'n/-{,n}cpio/f/' \
                 'n/-exec/c/' 'n/-ok/c/' 'n/-user/u/' \
                 'n/-group/g/' 'n/-fstype/(nfs 4.2)/' \
                 'n/-type/(b c d f l p s)/' \
                 'c/-/(name newer cpio ncpio exec ok user \
                 group fstype type atime ctime depth inum \
                 ls mtime nogroup nouser perm print prune \
                 size xdev)/' \

             This  completes  words  following `-name', `-newer',
             `-cpio' or `ncpio' (note the pattern  which  matches
             both)  to files, words following `-exec' or `-ok' to
             commands, words  following  `user'  and  `group'  to
             users  and  groups  respectively and words following
             `-fstype' or `-type' to members of the given  lists.
             It  also  completes the switches themselves from the

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User Commands                                             TCSH(1)

             given list (note the use of c-type  completion)  and
             completes  anything  not  otherwise  completed  to a
             directory.  Whew.

             Remember that programmed completions are ignored  if
             the  word  being  completed  is a tilde substitution
             (beginning with `~') or a variable  (beginning  with
             `$').   complete is an experimental feature, and the
             syntax may change in future versions of  the  shell.
             See also the uncomplete builtin command.

             Continues  execution  of the nearest enclosing while
             or foreach.  The rest of the commands on the current
             line are executed.

             Labels  the  default case in a switch statement.  It
             should come after all case labels.

     dirs [-l] [-n|-v]
     dirs -S|-L [filename] (+)
     dirs -c (+)
             The first form prints the directory stack.  The  top
             of  the stack is at the left and the first directory
             in the stack is the current directory.  With -l, `~'
             or  `~name'  in the output is expanded explicitly to
             home or the pathname of the home directory for  user
             name.   (+) With -n, entries are wrapped before they
             reach the edge of the screen.  (+) With -v,  entries
             are  printed  one  per line, preceded by their stack
             positions.  (+) If more than one  of  -n  or  -v  is
             given, -v takes precedence.  -p is accepted but does

             With -S, the second form saves the  directory  stack
             to  filename  as  a series of cd and pushd commands.
             With -L, the shell sources filename, which  is  pre-
             sumably  a  directory  stack  file  saved  by the -S
             option or the savedirs mechanism.  In  either  case,
             dirsfile  is  used  if  filename  is  not  given and
             ~/.cshdirs is used if dirsfile is unset.

             Note that login shells do the  equivalent  of  `dirs
             -L'  on  startup  and, if savedirs is set, `dirs -S'
             before exiting.  Because only ~/.tcshrc is  normally
             sourced before ~/.cshdirs, dirsfile should be set in
             ~/.tcshrc rather than ~/.login.

             The last form clears the directory stack.

     echo [-n] word ...

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User Commands                                             TCSH(1)

             Writes each word to  the  shell's  standard  output,
             separated  by  spaces and terminated with a newline.
             The echo_style shell variable may be set to  emulate
             (or  not)  the flags and escape sequences of the BSD
             and/or System V versions of echo; see echo(1).

     echotc [-sv] arg ... (+)
             Exercises  the  terminal  capabilities   (see   ter-
             minfo(4)) in args.  For example, 'echotc home' sends
             the cursor to the home position, 'echotc  cm  3  10'
             sends  it  to column 3 and row 10, and 'echotc ts 0;
             echo "This is a test."; echotc fs' prints "This is a
             test."  in the status line.

             If arg is 'baud', 'cols', 'lines', 'meta' or 'tabs',
             prints the value of that capability ("yes"  or  "no"
             indicating  that  the terminal does or does not have
             that capability).  One might use this  to  make  the
             output from a shell script less verbose on slow ter-
             minals, or limit command output  to  the  number  of
             lines on the screen:

                 > set history=`echotc lines`
                 > @ history--

             Termcap strings may contain wildcards which will not
             echo correctly.  One should use double  quotes  when
             setting  a  shell  variable to a terminal capability
             string, as in the following example that places  the
             date in the status line:

                 > set tosl="`echotc ts 0`"
                 > set frsl="`echotc fs`"
                 > echo -n "$tosl";date; echo -n "$frsl"

             With  -s,  nonexistent capabilities return the empty
             string rather than causing an error.  With -v,  mes-
             sages are verbose.

     endsw   See  the description of the foreach, if, switch, and
             while statements below.

     eval arg ...
             Treats the arguments as input to the shell and  exe-
             cutes the resulting command(s) in the context of the
             current shell.  This is usually used to execute com-
             mands generated as the result of command or variable
             substitution, because parsing  occurs  before  these
             substitutions.   See  tset(1B)  for  a sample use of

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User Commands                                             TCSH(1)


     exec command
             Executes the specified command in place of the  cur-
             rent shell.

     exit [expr]
             The  shell exits either with the value of the speci-
             fied expr (an expression, as described under Expres-
             sions) or, without expr, with the value 0.

     fg [%job ...]
             Brings  the  specified  jobs (or, without arguments,
             the current job)  into  the  foreground,  continuing
             each  if  it  is  stopped.   job  may be a number, a
             string, `', `%', `+' or `-' as described under Jobs.
             See also the run-fg-editor editor command.

     filetest -op file ... (+)
             Applies  op  (which  is  a  file inquiry operator as
             described under File inquiry operators) to each file
             and returns the results as a space-separated list.

     foreach name (wordlist)
     end     Successively  sets  the variable name to each member
             of wordlist and executes the  sequence  of  commands
             between  this  command  and the matching end.  (Both
             foreach  and  end  must  appear  alone  on  separate
             lines.)  The builtin command continue may be used to
             continue the loop prematurely and the  builtin  com-
             mand  break  to terminate it prematurely.  When this
             command is read from the terminal, the loop is  read
             once  prompting with `foreach? ' (or prompt2) before
             any statements in the loop  are  executed.   If  you
             make  a mistake typing in a loop at the terminal you
             can rub it out.

     getspath (+)
             Prints the system execution path.  (TCF only)

     getxvers (+)
             Prints the experimental version prefix.  (TCF only)

     glob wordlist
             Like echo, but the `-n' parameter is not  recognized
             and  words  are  delimited by null characters in the
             output.  Useful for programs which wish to  use  the
             shell to filename expand a list of words.

     goto word
             word  is filename and command-substituted to yield a

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User Commands                                             TCSH(1)

             string of the form `label'.  The shell  rewinds  its
             input  as  much  as possible, searches for a line of
             the form `label:', possibly preceded  by  blanks  or
             tabs, and continues execution after that line.

             Prints  a  statistics  line indicating how effective
             the internal hash table has been  at  locating  com-
             mands  (and  avoiding exec's).  An exec is attempted
             for each component of the path where the hash  func-
             tion indicates a possible hit, and in each component
             which does not begin with a `/'.

             On machines without vfork(2), prints only the number
             and size of hash buckets.

     history [-hTr] [n]
     history -S|-L|-M [filename] (+)
     history -c (+)
             The  first form prints the history event list.  If n
             is given only the n most recent events  are  printed
             or  saved.   With  -h,  the  history list is printed
             without leading numbers.  If -T is specified,  time-
             stamps  are printed also in comment form.  (This can
             be used to produce files suitable for  loading  with
             'history -L' or 'source -h'.)  With -r, the order of
             printing is most recent  first  rather  than  oldest

             With  -S,  the second form saves the history list to
             filename.  If the first word of the  savehist  shell
             variable is set to a number, at most that many lines
             are saved.  If the second word of savehist is set to
             `merge',  the history list is merged with the exist-
             ing history file instead of replacing it  (if  there
             is  one)  and  sorted by time stamp.  (+) Merging is
             intended for an environment like the X Window System
             with  several shells in simultaneous use.  Currently
             it succeeds only when the  shells  quit  nicely  one
             after another.

             With  -L,  the shell appends filename, which is pre-
             sumably a history list saved by the -S option or the
             savehist mechanism, to the history list.  -M is like
             -L, but the contents of filename are merged into the
             history  list  and  sorted  by timestamp.  In either
             case, histfile is used if filename is not given  and
             ~/.history  is  used if histfile is unset.  `history
             -L' is exactly like 'source -h' except that it  does
             not require a filename.

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User Commands                                             TCSH(1)

             Note that login shells do the equivalent of `history
             -L' on startup and, if savehist is set, `history -S'
             before  exiting.  Because only ~/.tcshrc is normally
             sourced before ~/.history, histfile should be set in
             ~/.tcshrc rather than ~/.login.

             If  histlit is set, the first and second forms print
             and save the literal (unexpanded) form of  the  his-
             tory list.

             The last form clears the history list.

     hup [command] (+)
             With command, runs command such that it will exit on
             a hangup signal and arranges for the shell  to  send
             it  a hangup signal when the shell exits.  Note that
             commands may set  their  own  response  to  hangups,
             overriding  hup.   Without  an  argument, causes the
             non-interactive shell only to exit on a  hangup  for
             the  remainder  of the script.  See also Signal han-
             dling and the nohup builtin command.

     if (expr) command
             If expr (an expression, as described  under  Expres-
             sions)  evaluates  true,  then  command is executed.
             Variable substitution on command happens  early,  at
             the  same  time  it does for the rest of the if com-
             mand.  command must be  a  simple  command,  not  an
             alias, a pipeline, a command list or a parenthesized
             command list, but it may have arguments.  Input/out-
             put  redirection  occurs  even  if expr is false and
             command is thus not executed; this is a bug.

     if (expr) then
     else if (expr2) then
     endif   If the specified expr is true then the  commands  to
             the  first  else are executed; otherwise if expr2 is
             true then the commands to the second else  are  exe-
             cuted,  etc.  Any number of else-if pairs are possi-
             ble; only one endif is needed.   The  else  part  is
             likewise  optional.   (The words else and endif must
             appear at the beginning of input lines; the if  must
             appear alone on its input line or after an else.)

     inlib shared-library ... (+)
             Adds each shared-library to the current environment.
             There  is  no  way  to  remove  a  shared   library.
             (Domain/OS only)

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User Commands                                             TCSH(1)

     jobs [-l]
             Lists  the  active jobs.  With -l, lists process IDs
             in addition to the normal information.  On TCF  sys-
             tems,  prints  the site on which each job is execut-

     kill [-s signal] %job|pid ...
     kill -l The first and second forms sends the specified  sig-
             nal (or, if none is given, the TERM (terminate) sig-
             nal) to the specified jobs or processes.  job may be
             a number, a string, `', `%', `+' or `-' as described
             under Jobs.  Signals are either given by  number  or
             by name (as given in /usr/include/signal.h, stripped
             of the prefix `SIG').  There is no default job; say-
             ing  just  `kill' does not send a signal to the cur-
             rent job.  If the signal being sent is TERM  (termi-
             nate)  or  HUP  (hangup), then the job or process is
             sent a CONT (continue) signal as  well.   The  third
             form lists the signal names.

     limit [-h] [resource [maximum-use]]
             Limits  the  consumption  by the current process and
             each process it creates to not  individually  exceed
             maximum-use  on the specified resource.  If no maxi-
             mum-use is given, then the current limit is printed;
             if  no  resource  is given, then all limitations are
             given.  If the -h flag is given, the hard limits are
             used instead of the current limits.  The hard limits
             impose a ceiling on the values of the  current  lim-
             its.  Only the super-user may raise the hard limits,
             but a user may lower or  raise  the  current  limits
             within the legal range.

             Controllable  resources  currently  include (if sup-
             ported by the OS):

                  the maximum number of cpu-seconds to be used by
                  each process

                  the largest single file which can be created

                  the maximum growth of the data+stack region via
                  sbrk(2) beyond the end of the program text

                  the maximum size of the  automatically-extended
                  stack region


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User Commands                                             TCSH(1)

                  the  size of the largest core dump that will be

                  the maximum amount of physical memory a process
                  may have allocated to it at a given time

                  the  maximum amount of virtual memory a process
                  may have  allocated  to  it  at  a  given  time
                  (address space)

                  the  maximum amount of virtual memory a process
                  may have allocated to it at a given time

                  the maximum amount  of  memory  a  process  may
                  allocate per brk() system call

             descriptors or openfiles
                  the  maximum  number  of  open  files  for this

                  the maximum number of threads for this process

                  the maximum size which a process may lock  into
                  memory using mlock(2)

                  the  maximum  number  of simultaneous processes
                  for this user id

                  the maximum size of  socket  buffer  usage  for
                  this user

                  the  maximum  amount  of swap space reserved or
                  used for this user

                  the maximum number of locks for this user

                  the maximum number of pending signals for  this

                  the  maximum  number  of bytes in POSIX mqueues

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User Commands                                             TCSH(1)

                  for this user

                  the maximum nice priority the user  is  allowed
                  to raise mapped from [19...-20] to [0...39] for
                  this user

                  the maximum realtime  priority  for  this  user
                  maxrttime the timeout for RT tasks in microsec-
                  onds for this user.

             maximum-use may be given as  a  (floating  point  or
             integer) number followed by a scale factor.  For all
             limits other than cputime the default scale  is  `k'
             or  `kilobytes'  (1024 bytes); a scale factor of `m'
             or `megabytes' or `g' or  `gigabytes'  may  also  be
             used.  For cputime the default scaling is `seconds',
             while `m' for minutes or `h' for hours, or a time of
             the  form  `mm:ss' giving minutes and seconds may be

             If maximum-use  is `unlimited', then the  limitation
             on the specified resource is removed (this is equiv-
             alent to the unlimit builtin command).

             For both resource names and scale factors, unambigu-
             ous prefixes of the names suffice.

     log (+) Prints  the watch shell variable and reports on each
             user indicated in watch who is logged in, regardless
             of when they last logged in.  See also watchlog.

     login   Terminates  a  login  shell,  replacing  it  with an
             instance of /bin/login. This is one way to log  off,
             included for compatibility with sh(1).

     logout  Terminates  a  login  shell.   Especially  useful if
             ignoreeof is set.

     ls-F [-switch ...] [file ...] (+)
             Lists files like `ls -F', but much faster.  It iden-
             tifies each type of special file in the listing with
             a special character:

             /   Directory
             *   Executable
             #   Block device
             %   Character device
             |   Named pipe (systems with named pipes only)
             =   Socket (systems with sockets only)
             @   Symbolic link (systems with symbolic links only)

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User Commands                                             TCSH(1)

             +   Hidden directory (AIX only) or context dependent
                 (HP/UX only)
             :   Network special (HP/UX only)

             If the listlinks shell  variable  is  set,  symbolic
             links are identified in more detail (on only systems
             that have them, of course):

             @   Symbolic link to a non-directory
             >   Symbolic link to a directory
             &   Symbolic link to nowhere

             listlinks also slows down ls-F and causes partitions
             holding  files  pointed  to  by symbolic links to be

             If the listflags shell variable is set to  `x',  `a'
             or  `A',  or  any  combination thereof (e.g., `xA'),
             they are used as flags to ls-F, making it  act  like
             `ls -xF', `ls -Fa', `ls -FA' or a combination (e.g.,
             `ls -FxA').  On machines where `ls -C'  is  not  the
             default,  ls-F  acts like `ls -CF', unless listflags
             contains an `x', in which  case  it  acts  like  `ls
             -xF'.   ls-F  passes its arguments to ls(1) if it is
             given any switches, so  `alias  ls  ls-F'  generally
             does the right thing.

             The ls-F builtin can list files using different col-
             ors depending on the filetype or extension.  See the
             color  shell  variable and the LS_COLORS environment

     migrate [-site] pid|%jobid ... (+)
     migrate -site (+)
             The first form migrates the process or  job  to  the
             site specified or the default site determined by the
             system path.   The  second  form  is  equivalent  to
             `migrate  -site $$': it migrates the current process
             to the specified site.  Migrating the  shell  itself
             can  cause  unexpected  behavior,  because the shell
             does not like to lose its tty.  (TCF only)

     newgrp [-] [group] (+)
             Equivalent to `exec newgrp'; see newgrp(1).   Avail-
             able only if the shell was so compiled; see the ver-
             sion shell variable.

     nice [+number] [command]
             Sets the scheduling priority for the shell  to  num-
             ber,  or,  without number, to 4.  With command, runs
             command at the appropriate  priority.   The  greater
             the  number,  the  less  cpu  the process gets.  The

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User Commands                                             TCSH(1)

             super-user may specify negative  priority  by  using
             `nice -number ...'.  Command is always executed in a
             sub-shell, and the restrictions placed  on  commands
             in simple if statements apply.

     nohup [command]
             With  command, runs command such that it will ignore
             hangup signals.  Note that commands  may  set  their
             own  response to hangups, overriding nohup.  Without
             an argument, causes the non-interactive  shell  only
             to  ignore  hangups for the remainder of the script.
             See also Signal handling and the  hup  builtin  com-

     notify [%job ...]
             Causes  the  shell to notify the user asynchronously
             when the status of any of the  specified  jobs  (or,
             without  %job,  the current job) changes, instead of
             waiting until the next prompt as is usual.  job  may
             be  a  number,  a  string,  `',  `%',  `+' or `-' as
             described under Jobs.  See  also  the  notify  shell

     onintr [-|label]
             Controls  the  action  of  the  shell on interrupts.
             Without arguments, restores the  default  action  of
             the shell on interrupts, which is to terminate shell
             scripts or to return to the terminal  command  input
             level.   With  `-',  causes  all  interrupts  to  be
             ignored.  With label, causes the shell to execute  a
             `goto  label'  when  an  interrupt  is received or a
             child process terminates because it was interrupted.

             onintr  is  ignored if the shell is running detached
             and in  system  startup  files  (see  FILES),  where
             interrupts are disabled anyway.

     popd [-p] [-l] [-n|-v] [+n]
             Without  arguments,  pops  the  directory  stack and
             returns to the new top  directory.   With  a  number
             `+n', discards the n'th entry in the stack.

             Finally, all forms of popd print the final directory
             stack, just like dirs.  The pushdsilent shell  vari-
             able  can be set to prevent this and the -p flag can
             be given to override pushdsilent.  The -l, -n and -v
             flags have the same effect on popd as on dirs.  (+)

     printenv [name] (+)
             Prints the names and values of all environment vari-
             ables or, with name, the value  of  the  environment
             variable name.

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User Commands                                             TCSH(1)

     pushd [-p] [-l] [-n|-v] [name|+n]
             Without arguments, exchanges the top two elements of
             the directory stack.  If pushdtohome is  set,  pushd
             without arguments does `pushd ~', like cd.  (+) With
             name, pushes the current working directory onto  the
             directory stack and changes to name.  If name is `-'
             it is interpreted as the previous working  directory
             (see Filename substitution).  (+) If dunique is set,
             pushd removes any instances of name from  the  stack
             before pushing it onto the stack.  (+) With a number
             `+n', rotates the nth element of the directory stack
             around  to be the top element and changes to it.  If
             dextract is set, however, `pushd  +n'  extracts  the
             nth  directory,  pushes it onto the top of the stack
             and changes to it.  (+)

             Finally, all forms of pushd print the  final  direc-
             tory  stack,  just like dirs.  The pushdsilent shell
             variable can be set to prevent this and the -p  flag
             can  be  given  to override pushdsilent.  The -l, -n
             and -v flags have the same effect  on  pushd  as  on
             dirs.  (+)

     rehash  Causes  the  internal  hash table of the contents of
             the directories in the path variable  to  be  recom-
             puted.  This is needed if the autorehash shell vari-
             able is not set and new commands are added to direc-
             tories  in  path  while  you  are  logged  in.  With
             autorehash, a new command will  be  found  automati-
             cally, except in the special case where another com-
             mand of the same name which is located in a  differ-
             ent  directory  already  exists  in  the hash table.
             Also flushes the cache of home directories built  by
             tilde expansion.

     repeat count command
             The  specified command, which is subject to the same
             restrictions as the  command  in  the  one  line  if
             statement above, is executed count times.  I/O redi-
             rections occur exactly once, even if count is 0.

     rootnode //nodename (+)
             Changes the rootnode to //nodename, so that `/' will
             be interpreted as `//nodename'.  (Domain/OS only)

     sched (+)
     sched [+]hh:mm command (+)
     sched -n (+)
             The first form prints the scheduled-event list.  The
             sched shell variable may be set to define the format
             in  which  the scheduled-event list is printed.  The
             second form  adds  command  to  the  scheduled-event

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User Commands                                             TCSH(1)

             list.  For example,

                 > sched 11:00 echo It\'s eleven o\'clock.

             causes  the  shell to echo `It's eleven o'clock.' at
             11 AM.  The time may be in 12-hour AM/PM format

                 > sched 5pm set prompt='[%h] It\'s after  5;  go
                 home: >'

             or may be relative to the current time:

                 > sched +2:15 /usr/lib/uucp/uucico -r1 -sother

             A relative time specification may not use AM/PM for-
             mat.  The third form removes item n from  the  event

                 > sched
                      1   Wed  Apr  4 15:42  /usr/lib/uucp/uucico
                 -r1 -sother
                      2  Wed Apr  4 17:00  set  prompt=[%h]  It's
                 after 5; go home: >
                 > sched -2
                 > sched
                      1   Wed  Apr  4 15:42  /usr/lib/uucp/uucico
                 -r1 -sother

             A command in the scheduled-event  list  is  executed
             just  before  the  first prompt is printed after the
             time when the command is scheduled.  It is  possible
             to  miss  the  exact  time when the command is to be
             run, but an overdue command will execute at the next
             prompt.   A  command which comes due while the shell
             is waiting for user input is  executed  immediately.
             However, normal operation of an already-running com-
             mand will not be interrupted so  that  a  scheduled-
             event list element may be run.

             This  mechanism  is similar to, but not the same as,
             the at(1) command on some Unix systems.   Its  major
             disadvantage  is  that  it  may not run a command at
             exactly the specified time.  Its major advantage  is
             that  because sched runs directly from the shell, it
             has access to shell variables and other  structures.
             This provides a mechanism for changing one's working
             environment based on the time of day.

     set name ...
     set name=word ...
     set [-r] [-f|-l] name=(wordlist) ... (+)

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User Commands                                             TCSH(1)

     set name[index]=word ...
     set -r (+)
     set -r name ... (+)
     set -r name=word ... (+)
             The first form of the command prints  the  value  of
             all  shell  variables.  Variables which contain more
             than a single word print  as  a  parenthesized  word
             list.  The second form sets name to the null string.
             The third form sets name to the  single  word.   The
             fourth  form  sets  name  to  the  list  of words in
             wordlist.  In all cases the  value  is  command  and
             filename expanded.  If -r is specified, the value is
             set read-only.  If -f or -l are specified, set  only
             unique  words  keeping  their order.  -f prefers the
             first occurrence of a word, and -l  the  last.   The
             fifth  form  sets  the index'th component of name to
             word; this component must already exist.  The  sixth
             form  lists  only  the  names of all shell variables
             that are read-only.  The  seventh  form  makes  name
             read-only,  whether  or  not  it  has  a value.  The
             eighth form is the same as the third form, but  make
             name read-only at the same time.

             These  arguments  can be repeated to set and/or make
             read-only multiple variables in a  single  set  com-
             mand.   Note,  however, that variable expansion hap-
             pens for all arguments before  any  setting  occurs.
             Note  also that `=' can be adjacent to both name and
             word or separated from both by whitespace, but  can-
             not  be adjacent to only one or the other.  See also
             the unset builtin command.

     setenv [name [value]]
             Without arguments, prints the names  and  values  of
             all  environment  variables.   Given  name, sets the
             environment  variable  name  to  value  or,  without
             value, to the null string.

     setpath path (+)
             Equivalent to setpath(1).  (Mach only)

     setspath LOCAL|site|cpu ... (+)
             Sets the system execution path.  (TCF only)

     settc cap value (+)
             Tells  the  shell to believe that the terminal capa-
             bility cap (as defined in terminfo(4)) has the value
             value.   No sanity checking is done.  Concept termi-
             nal users may have to `settc xn no'  to  get  proper
             wrapping at the rightmost column.

     setty [-d|-q|-x] [-a] [[+|-]mode] (+)

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User Commands                                             TCSH(1)

             Controls  which  tty modes (see Terminal management)
             the shell does not allow to change.  -d,  -q  or  -x
             tells  setty  to act on the `edit', `quote' or `exe-
             cute' set of tty modes respectively; without -d,  -q
             or -x, `execute' is used.

             Without  other  arguments,  setty lists the modes in
             the chosen set which are fixed on (`+mode')  or  off
             (`-mode').   The  available modes, and thus the dis-
             play, vary from system to system.   With  -a,  lists
             all  tty modes in the chosen set whether or not they
             are fixed.  With +mode, -mode or mode, fixes mode on
             or  off  or  removes control from mode in the chosen
             set.   For  example,  `setty  +echok  echoe'   fixes
             `echok'  mode on and allows commands to turn `echoe'
             mode on or off, both when  the  shell  is  executing

     setxvers [string] (+)
             Set  the  experimental  version prefix to string, or
             removes it if string is omitted.  (TCF only)

     shift [variable]
             Without arguments, discards argv[1] and  shifts  the
             members  of  argv  to  the left.  It is an error for
             argv not to be set or to have less than one word  as
             value.  With variable, performs the same function on

     source [-h] name [args ...]
             The shell reads and  executes  commands  from  name.
             The commands are not placed on the history list.  If
             any args are given, they are placed  in  argv.   (+)
             source  commands  may  be nested; if they are nested
             too deeply the shell may run out  of  file  descrip-
             tors.   An error in a source at any level terminates
             all nested source commands.  With -h,  commands  are
             placed  on  the  history  list instead of being exe-
             cuted, much like `history -L'.

     stop %job|pid ...
             Stops the specified jobs or processes which are exe-
             cuting  in  the  background.  job may be a number, a
             string, `', `%', `+' or `-' as described under Jobs.
             There is no default job; saying just `stop' does not
             stop the current job.

     suspend Causes the shell to stop in its tracks, much  as  if
             it  had  been  sent  a stop signal with ^Z.  This is
             most often used to stop shells started by su(1M).

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User Commands                                             TCSH(1)

     switch (string)
     case str1:
     endsw   Each case label is successively matched, against the
             specified string which is first command and filename
             expanded.  The  file  metacharacters  `*',  `?'  and
             `[...]'   may  be used in the case labels, which are
             variable expanded.  If  none  of  the  labels  match
             before  a  `default' label is found, then the execu-
             tion begins after  the  default  label.   Each  case
             label  and  the  default  label  must  appear at the
             beginning of a line.   The  command  breaksw  causes
             execution  to  continue  after the endsw.  Otherwise
             control may fall through  case  labels  and  default
             labels as in C.  If no label matches and there is no
             default, execution continues after the endsw.

     telltc (+)
             Lists the values of all terminal  capabilities  (see

     termname [terminal type] (+)
             Tests if terminal type (or the current value of TERM
             if no terminal type is given) has an  entry  in  the
             hosts terminfo(4) database. Prints the terminal type
             to stdout and returns 0 if an entry is present  oth-
             erwise returns 1.

     time [command]
             Executes  command  (which  must be a simple command,
             not an alias, a pipeline, a command list or a paren-
             thesized  command list) and prints a time summary as
             described under the time variable.  If necessary, an
             extra  shell  is created to print the time statistic
             when the command completes.  Without command, prints
             a  time  summary for the current shell and its chil-

     umask [value]
             Sets the file creation mask to value, which is given
             in  octal.  Common values for the mask are 002, giv-
             ing all access to the group  and  read  and  execute
             access  to  others, and 022, giving read and execute
             access to the  group  and  others.   Without  value,
             prints the current file creation mask.

     unalias pattern

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User Commands                                             TCSH(1)

             Removes  all  aliases  whose  names  match  pattern.
             `unalias *' thus removes all aliases.  It is not  an
             error for nothing to be unaliased.

     uncomplete pattern (+)
             Removes  all  completions whose names match pattern.
             `uncomplete *' thus removes all completions.  It  is
             not an error for nothing to be uncompleted.

     unhash  Disables  use  of  the  internal hash table to speed
             location of executed programs.

     universe universe (+)
             Sets the universe to universe.  (Masscomp/RTU only)

     unlimit [-hf] [resource]
             Removes  the  limitation  on  resource  or,  if   no
             resource  is  specified,  all  resource limitations.
             With -h, the corresponding hard limits are  removed.
             Only  the super-user may do this.  Note that unlimit
             may not exit successful, since most systems  do  not
             allow  descriptors  to be unlimited.  With -f errors
             are ignored.

     unset pattern
             Removes all variables  whose  names  match  pattern,
             unless  they  are read-only.  `unset *' thus removes
             all variables unless they are read-only; this  is  a
             bad  idea.   It  is  not  an error for nothing to be

     unsetenv pattern
             Removes all environment variables whose names  match
             pattern.   `unsetenv *' thus removes all environment
             variables; this is a bad idea.  It is not  an  error
             for nothing to be unsetenved.

     ver [systype [command]] (+)
             Without  arguments,  prints  SYSTYPE.  With systype,
             sets SYSTYPE to systype.  With systype and  command,
             executes  command  under  systype.   systype  may be
             `bsd4.3' or `sys5.3'.  (Domain/OS only)

     wait    The shell waits for all  background  jobs.   If  the
             shell  is interactive, an interrupt will disrupt the
             wait and cause the shell to print the names and  job
             numbers of all outstanding jobs.

     warp universe (+)
             Sets the universe to universe.  (Convex/OS only)

     watchlog (+)

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User Commands                                             TCSH(1)

             An  alternate  name  for  the  log  builtin  command
             (q.v.).  Available only if the  shell  was  so  com-
             piled; see the version shell variable.

     where command (+)
             Reports  all  known  instances of command, including
             aliases, builtins and executables in path.

     which command (+)
             Displays the command that will be  executed  by  the
             shell after substitutions, path searching, etc.  The
             builtin command is just like which(1), but  it  cor-
             rectly  reports  tcsh aliases and builtins and is 10
             to 100 times faster.   See  also  the  which-command
             editor command.

     while (expr)
     end     Executes  the  commands  between  the  while and the
             matching end while expr (an expression, as described
             under  Expressions)  evaluates  non-zero.  while and
             end must appear alone on their input  lines.   break
             and  continue  may  be used to terminate or continue
             the loop prematurely.  If the input is  a  terminal,
             the user is prompted the first time through the loop
             as with foreach.

  Special aliases (+)
     If set, each of these aliases executes automatically at  the
     indicated time.  They are all initially undefined.

     beepcmd Runs when the shell wants to ring the terminal bell.

     cwdcmd  Runs after every change of working  directory.   For
             example,  if the user is working on an X window sys-
             tem using xterm(1) and a re-parenting window manager
             that supports title bars such as twm(1) and does

                 > alias cwdcmd  'echo -n "^[]2;${HOST}:$cwd ^G"'

             then the shell will change the title of the  running
             xterm(1)  to  be  the name of the host, a colon, and
             the full current working directory.  A  fancier  way
             to do that is

                 >        alias       cwdcmd       'echo       -n

             This will put the hostname and working directory  on
             the title bar but only the hostname in the icon man-
             ager menu.

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             Note that putting a cd, pushd or popd in cwdcmd  may
             cause  an infinite loop.  It is the author's opinion
             that anyone doing so will get what they deserve.

     jobcmd  Runs before each command gets executed, or when  the
             command  changes state.  This is similar to postcmd,
             but it does not print builtins.

                 > alias jobcmd  'echo -n "^[]2\;\!#:q^G"'

             then executing vi foo.c will put the command  string
             in the xterm title bar.

             Invoked by the run-help editor command.  The command
             name for which help is  sought  is  passed  as  sole
             argument.  For example, if one does

                 > alias helpcommand '\!:1 --help'

             then  the help display of the command itself will be
             invoked, using  the  GNU  help  calling  convention.
             Currently  there is no easy way to account for vari-
             ous calling conventions (e.g.,  the  customary  Unix
             `-h'), except by using a table of many commands.

             Runs  every tperiod minutes.  This provides a conve-
             nient means for checking on  common  but  infrequent
             changes such as new mail.  For example, if one does

                 > set tperiod = 30
                 > alias periodic checknews

             then the checknews(1) program runs every 30 minutes.
             If periodic is set but tperiod is unset or set to 0,
             periodic behaves like precmd.

     precmd  Runs  just before each prompt is printed.  For exam-
             ple, if one does

                 > alias precmd date

             then date(1) runs just before the shell prompts  for
             each  command.   There  are no limits on what precmd
             can be set to do, but discretion should be used.

     postcmd Runs before each command gets executed.

                 > alias postcmd  'echo -n "^[]2\;\!#:q^G"'

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User Commands                                             TCSH(1)

             then executing vi foo.c will put the command  string
             in the xterm title bar.

     shell   Specifies  the  interpreter  for  executable scripts
             which do not themselves specify an interpreter.  The
             first word should be a full path name to the desired
             interpreter       (e.g.,        `/bin/csh'        or

  Special shell variables
     The variables described in this section have special meaning
     to the shell.

     The shell sets addsuffix, argv, autologout, csubstnonl, com-
     mand,  echo_style,  edit,  gid,  group,  home, loginsh, oid,
     path, prompt, prompt2, prompt3, shell,  shlvl,  tcsh,  term,
     tty,  uid,  user  and version at startup; they do not change
     thereafter unless changed by the user.   The  shell  updates
     cwd,  dirstack,  owd  and  status  when  necessary, and sets
     logout on logout.

     The shell synchronizes group, home, path,  shlvl,  term  and
     user with the environment variables of the same names: when-
     ever the environment variable changes the shell changes  the
     corresponding  shell  variable  to  match  (unless the shell
     variable is read-only) and vice versa.  Note  that  although
     cwd  and  PWD have identical meanings, they are not synchro-
     nized in this  manner,  and  that  the  shell  automatically
     interconverts the different formats of path and PATH.

     addsuffix (+)
             If  set,  filename completion adds `/' to the end of
             directories and a space to the end of  normal  files
             when they are matched exactly.  Set by default.

     afsuser (+)
             If set, autologout's autolock feature uses its value
             instead of the local username for kerberos authenti-

     ampm (+)
             If set, all times are shown in 12-hour AM/PM format.

     argv    The arguments to the shell.   Positional  parameters
             are  taken  from  argv,  i.e.,  `$1'  is replaced by
             `$argv[1]', etc.  Set by default, but usually  empty
             in interactive shells.

     autocorrect (+)
             If  set,  the  spell-word  editor command is invoked
             automatically before each completion attempt.

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User Commands                                             TCSH(1)

     autoexpand (+)
             If set, the expand-history editor command is invoked
             automatically  before  each  completion  attempt. If
             this is set to onlyhistory, then only  history  will
             be  expanded  and  a  second  completion will expand

     autolist (+)
             If set, possibilities are listed after an  ambiguous
             completion.   If  set  to `ambiguous', possibilities
             are listed only when no new characters are added  by

     autologout (+)
             The  first word is the number of minutes of inactiv-
             ity before automatic logout.   The  optional  second
             word  is  the number of minutes of inactivity before
             automatic locking.   When  the  shell  automatically
             logs out, it prints `auto-logout', sets the variable
             logout to `automatic' and  exits.   When  the  shell
             automatically  locks,  the user is required to enter
             his password to continue  working.   Five  incorrect
             attempts  result  in  automatic logout.  Set to `60'
             (automatic logout after 60 minutes, and no  locking)
             by default in login and superuser shells, but not if
             the shell thinks it is running under a window system
             (i.e., the DISPLAY environment variable is set), the
             tty is a pseudo-tty (pty) or the shell  was  not  so
             compiled (see the version shell variable).  See also
             the afsuser and logout shell variables.

     autorehash (+)
             If set, the internal hash table of the  contents  of
             the  directories in the path variable will be recom-
             puted if a command is not found in the  hash  table.
             In  addition, the list of available commands will be
             rebuilt for each command completion or spelling cor-
             rection  attempt  if  set to `complete' or `correct'
             respectively; if set to `always', this will be  done
             for both cases.

     backslash_quote (+)
             If set, backslashes (`\') always quote `\', `'', and
             `"'.  This may make complex  quoting  tasks  easier,
             but it can cause syntax errors in csh(1) scripts.

     catalog The  file name of the message catalog.  If set, tcsh
             use `tcsh.${catalog}' as a message  catalog  instead
             of default `tcsh'.

     cdpath  A  list of directories in which cd should search for
             subdirectories if they aren't found in  the  current

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User Commands                                             TCSH(1)


     color   If  set,  it  enables  color display for the builtin
             ls-F and it passes  --color=auto  to  ls.   Alterna-
             tively,  it  can  be  set to only ls-F or only ls to
             enable color to only one  command.   Setting  it  to
             nothing is equivalent to setting it to (ls-F ls).

             If  set,  it  enables  color escape sequence for NLS
             message files.  And display colorful NLS messages.

     command (+)
             If set, the command which was passed  to  the  shell
             with the -c flag (q.v.).

     compat_expr (+)
             If set, the shell will evaluate expressions right to
             left, like the original csh.

     complete (+)
             If set to `igncase',  the  completion  becomes  case
             insensitive.    If   set  to  `enhance',  completion
             ignores case and considers hyphens  and  underscores
             to  be  equivalent;  it  will  also  treat  periods,
             hyphens and underscores (`.', `-' and `_')  as  word
             separators.  If set to `Enhance', completion matches
             uppercase and underscore characters  explicitly  and
             matches  lowercase and hyphens in a case-insensivite
             manner; it will treat  periods,  hypens  and  under-
             scores as word separators.

     continue (+)
             If  set  to  a list of commands, the shell will con-
             tinue the listed commands, instead of starting a new

     continue_args (+)
             Same as continue, but the shell will execute:

                 echo `pwd` $argv > ~/.<cmd>_pause; %<cmd>

     correct (+)
             If   set   to   `cmd',  commands  are  automatically
             spelling-corrected.  If set to `complete',  commands
             are  automatically  completed.  If set to `all', the
             entire command line is corrected.

     csubstnonl (+)
             If set, newlines and  carriage  returns  in  command
             substitution   are   replaced  by  spaces.   Set  by

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User Commands                                             TCSH(1)

     cwd     The full pathname of  the  current  directory.   See
             also the dirstack and owd shell variables.

     dextract (+)
             If  set,  `pushd +n' extracts the nth directory from
             the directory stack rather than rotating it  to  the

     dirsfile (+)
             The  default  location  in which `dirs -S' and `dirs
             -L' look for a history file.  If  unset,  ~/.cshdirs
             is used.  Because only ~/.tcshrc is normally sourced
             before  ~/.cshdirs,  dirsfile  should  be   set   in
             ~/.tcshrc rather than ~/.login.

     dirstack (+)
             An  array  of  all  the directories on the directory
             stack.  `$dirstack[1]' is the current working direc-
             tory,  `$dirstack[2]'  the  first  directory  on the
             stack, etc.  Note that the current working directory
             is  `$dirstack[1]'  but `=0' in directory stack sub-
             stitutions, etc.  One can change the stack arbitrar-
             ily  by setting dirstack, but the first element (the
             current working directory) is always  correct.   See
             also the cwd and owd shell variables.

     dspmbyte (+)
             Has  an  effect  iff 'dspm' is listed as part of the
             version shell variable.  If set to `euc', it enables
             display  and  editing  EUC-kanji(Japanese) code.  If
             set to `sjis', it enables display and editing Shift-
             JIS(Japanese)  code.   If  set to `big5', it enables
             display and editing Big5(Chinese) code.  If  set  to
             `utf8', it enables display and editing Utf8(Unicode)
             code.  If set to the following  format,  it  enables
             display and editing of original multi-byte code for-

                 > set dspmbyte = 0000....(256 bytes)....0000

             The table requires just 256 bytes.   Each  character
             of  256  characters corresponds (from left to right)
             to the ASCII codes 0x00, 0x01, ... 0xff.  Each char-
             acter is set to number 0,1,2 and 3.  Each number has
             the following meaning:
               0 ... not used for multi-byte characters.
               1 ... used for the  first  byte  of  a  multi-byte
               2  ...  used  for  the second byte of a multi-byte
               3 ... used for both the first byte and second byte
             of a multi-byte character.

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User Commands                                             TCSH(1)

             If  set to `001322', the first character (means 0x00
             of the ASCII code) and second character (means  0x01
             of ASCII code) are set to `0'.  Then, it is not used
             for multi-byte characters.  The 3rd character (0x02)
             is  set  to  '1', indicating that it is used for the
             first byte of a multi-byte character.  The 4th char-
             acter(0x03)  is  set  '3'.   It is used for both the
             first byte and the second byte of a multi-byte char-
             acter.   The  5th and 6th characters (0x04,0x05) are
             set to '2', indicating that they are  used  for  the
             second byte of a multi-byte character.

             The  GNU  fileutils  version  of  ls  cannot display
             multi-byte filenames without the -N  (  --literal  )
             option.    If  you  are  using this version, set the
             second word of dspmbyte to "ls".  If not, for  exam-
             ple,  "ls-F -l" cannot display multi-byte filenames.

             This variable can only be used if KANJI and DSPMBYTE
             has been defined at compile time.

     dunique (+)
             If set, pushd removes any instances of name from the
             stack before pushing it onto the stack.

     echo    If set, each command with its  arguments  is  echoed
             just  before  it  is executed.  For non-builtin com-
             mands all expansions occur before echoing.   Builtin
             commands are echoed before command and filename sub-
             stitution, because these substitutions are then done
             selectively.  Set by the -x command line option.

     echo_style (+)
             The style of the echo builtin.  May be set to

             bsd     Don't  echo  a newline if the first argument
                     is `-n'.
             sysv    Recognize backslashed  escape  sequences  in
                     echo strings.
             both    Recognize both the `-n' flag and backslashed
                     escape sequences; the default.
             none    Recognize neither.

             Set by default to the local system default.  The BSD
             and  System  V  options are described in the echo(1)
             man pages on the appropriate systems.

     edit (+)
             If set, the command-line editor  is  used.   Set  by
             default in interactive shells.

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User Commands                                             TCSH(1)

     ellipsis (+)
             If set, the `%c'/`%.' and `%C' prompt sequences (see
             the prompt shell variable) indicate skipped directo-
             ries   with   an   ellipsis   (`...')    instead  of

     euid (+)
             The user's effective user ID.

     euser (+)
             The first matching passwd entry  name  corresponding
             to the effective user ID.

     fignore (+)
             Lists  file  name  suffixes to be ignored by comple-

     filec   In tcsh, completion is always used and this variable
             is  ignored  by  default. If edit is unset, then the
             traditional csh completion is used.  If set in  csh,
             filename completion is used.

     gid (+) The user's real group ID.

     globdot (+)
             If set, wild-card glob patterns will match files and
             directories beginning with `.' except  for  `.'  and

     globstar (+)
             If  set,  the `**' and `***' file glob patterns will
             match  any  string  of  characters   including   `/'
             traversing any existing sub-directories.  (e.g.  `ls
             **.c' will list all the  .c  files  in  the  current
             directory  tree).   If used by itself, it will match
             match  zero  or  more  sub-directories   (e.g.   `ls
             /usr/include/**/time.h'  will  list  any  file named
             `time.h' in the /usr/include directory tree; whereas
             `ls  /usr/include/**time.h'  will  match any file in
             the /usr/include directory tree ending in `time.h').
             To  prevent  problems with recursion, the `**' glob-
             pattern will not descend into a symbolic  link  con-
             taining a directory.  To override this, use `***'

     group (+)
             The user's group name.

             If  set,  the incremental search match (in i-search-
             back and i-search-fwd) and the  region  between  the
             mark  and  the  cursor  are  highlighted  in reverse

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User Commands                                             TCSH(1)

             Highlighting requires more frequent terminal writes,
             which  introduces  extra overhead. If you care about
             terminal performance, you may  want  to  leave  this

             A  string  value  determining the characters used in
             History substitution (q.v.).  The first character of
             its  value is used as the history substitution char-
             acter, replacing the  default  character  `!'.   The
             second character of its value replaces the character
             `^' in quick substitutions.

     histdup (+)
             Controls handling of duplicate entries in  the  his-
             tory  list.   If  set  to  `all' only unique history
             events are entered in the history list.  If  set  to
             `prev' and the last history event is the same as the
             current command, then the  current  command  is  not
             entered  in  the history.  If set to `erase' and the
             same event is found in the history  list,  that  old
             event gets erased and the current one gets inserted.
             Note that the `prev' and `all' options renumber his-
             tory events so there are no gaps.

     histfile (+)
             The default location in which `history -S' and `his-
             tory -L' look for a history file.  If unset, ~/.his-
             tory  is  used.  histfile is useful when sharing the
             same home directory between different  machines,  or
             when  saving  separate histories on different termi-
             nals.  Because only ~/.tcshrc  is  normally  sourced
             before   ~/.history,   histfile  should  be  set  in
             ~/.tcshrc rather than ~/.login.

     histlit (+)
             If set, builtin and editor commands and the savehist
             mechanism use the literal (unexpanded) form of lines
             in the history list.  See also  the  toggle-literal-
             history editor command.

     history The  first  word  indicates  the  number  of history
             events to save.  The optional second word (+)  indi-
             cates the format in which history is printed; if not
             given, `%h\t%T\t%R\n' is used.  The format sequences
             are  described below under prompt; note the variable
             meaning of `%R'.  Set to `100' by default.

     home    Initialized to the home directory  of  the  invoker.
             The  filename  expansion of `~' refers to this vari-

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             If set to the empty string  or  `0'  and  the  input
             device  is a terminal, the end-of-file command (usu-
             ally generated by the user  by  typing  `^D'  on  an
             empty line) causes the shell to print `Use "exit" to
             leave tcsh.' instead of exiting.  This prevents  the
             shell  from accidentally being killed.  Historically
             this setting exited after  26  successive  EOF's  to
             avoid  infinite  loops.   If  set to a number n, the
             shell ignores n -  1  consecutive  end-of-files  and
             exits  on the nth.  (+) If unset, `1' is used, i.e.,
             the shell exits on a single `^D'.

     implicitcd (+)
             If set, the shell treats a directory name typed as a
             command  as  though  it  were a request to change to
             that directory.  If set to verbose,  the  change  of
             directory  is  echoed  to the standard output.  This
             behavior  is  inhibited  in  non-interactive   shell
             scripts,  or  for command strings with more than one
             word.  Changing directory takes precedence over exe-
             cuting  a  like-named  command, but it is done after
             alias substitutions.  Tilde and variable  expansions
             work as expected.

     inputmode (+)
             If  set  to `insert' or `overwrite', puts the editor
             into that input mode at the beginning of each  line.

     killdup (+)
             Controls  handling  of duplicate entries in the kill
             ring.  If set  to  `all'  only  unique  strings  are
             entered  in the kill ring.  If set to `prev' and the
             last killed string is the same as the current killed
             string,  then  the  current string is not entered in
             the ring.  If set to `erase' and the same string  is
             found in the kill ring, the old string is erased and
             the current one is inserted.

     killring (+)
             Indicates the number of killed strings  to  keep  in
             memory.  Set to `30' by default.  If unset or set to
             less than `2', the shell will  only  keep  the  most
             recently  killed  string.   Strings  are  put in the
             killring by the editor commands that  delete  (kill)
             strings  of  text,  e.g. backward-delete-word, kill-
             line, etc, as well as the  copy-region-as-kill  com-
             mand.   The  yank  editor command will yank the most
             recently killed string into the command-line,  while
             yank-pop  (see  Editor commands) can be used to yank
             earlier killed strings.

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     listflags (+)
             If set to  `x',  `a'  or  `A',  or  any  combination
             thereof  (e.g.,  `xA'),  they  are  used as flags to
             ls-F, making it act like `ls  -xF',  `ls  -Fa',  `ls
             -FA'  or  a combination (e.g., `ls -FxA'): `a' shows
             all files (even if they start with a `.'), `A' shows
             all  files  but  `.'  and `..', and `x' sorts across
             instead of down.  If the second word of listflags is
             set, it is used as the path to `ls(1)'.

     listjobs (+)
             If set, all jobs are listed when a job is suspended.
             If set to `long', the listing is in long format.

     listlinks (+)
             If set, the ls-F builtin command shows the  type  of
             file to which each symbolic link points.

     listmax (+)
             The  maximum  number of items which the list-choices
             editor command will list without asking first.

     listmaxrows (+)
             The maximum number of rows of items which the  list-
             choices  editor  command  will  list  without asking

     loginsh (+)
             Set by the shell if it is a login shell.  Setting or
             unsetting it within a shell has no effect.  See also

     logout (+)
             Set by the shell to `normal' before a normal logout,
             `automatic' before an automatic logout, and `hangup'
             if the shell was killed by a hangup signal (see Sig-
             nal  handling).  See also the autologout shell vari-

     mail    A list of files and directories to check for  incom-
             ing  mail,  optionally  preceded  by a numeric word.
             Before each prompt, if 10 minutes have passed  since
             the  last check, the shell checks each file and says
             `You have new mail.' (or, if mail contains  multiple
             files, `You have new mail in name.') if the filesize
             is greater than zero in size and has a  modification
             time greater than its access time.

             If  you  are  in a login shell, then no mail file is
             reported unless it has been modified after the  time
             the shell has started up, to prevent redundant noti-
             fications.   Most  login  programs  will  tell   you

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User Commands                                             TCSH(1)

             whether or not you have mail when you log in.

             If  a  file  specified  in  mail is a directory, the
             shell will count each file within that directory  as
             a  separate  message,  and  will  report `You have n
             mails.' or `You have n mails in name.' as  appropri-
             ate.   This  functionality is provided primarily for
             those systems which store mail in this manner,  such
             as the Andrew Mail System.

             If  the first word of mail is numeric it is taken as
             a different mail checking interval, in seconds.

             Under very rare circumstances, the shell may  report
             `You have mail.' instead of `You have new mail.'

     matchbeep (+)
             If  set  to `never', completion never beeps.  If set
             to `nomatch', it beeps only when there is no  match.
             If  set to `ambiguous', it beeps when there are mul-
             tiple matches.  If set to `notunique', it beeps when
             there  is  one  exact  and other longer matches.  If
             unset, `ambiguous' is used.

     nobeep (+)
             If set, beeping is completely  disabled.   See  also

             If  set, restrictions are placed on output redirect-
             ion  to  insure  that  files  are  not  accidentally
             destroyed and that `>>' redirections refer to exist-
             ing files, as described in the Input/output section.

     noding  If  set,  disable  the  printing  of  `DING!' in the
             prompt time specifiers at the change of hour.

     noglob  If set, Filename substitution  and  Directory  stack
             substitution  (q.v.)  are  inhibited.   This is most
             useful in shell scripts which do not deal with file-
             names,  or  after  a  list  of  filenames  has  been
             obtained and further expansions are not desirable.

     nokanji (+)
             If set and the shell supports Kanji (see the version
             shell variable), it is disabled so that the meta key
             can be used.

             If set, a Filename substitution or  Directory  stack
             substitution  (q.v.) which does not match any exist-
             ing files is left untouched rather than  causing  an

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User Commands                                             TCSH(1)

             error.  It is still an error for the substitution to
             be malformed, e.g., `echo [' still gives an error.

     nostat (+)
             A list of directories (or glob-patterns which  match
             directories;  see Filename substitution) that should
             not be  stat(2)ed  during  a  completion  operation.
             This  is  usually  used to exclude directories which
             take too much time to stat(2), for example /afs.

     notify  If set, the shell announces  job  completions  asyn-
             chronously.   The  default is to present job comple-
             tions just before printing a prompt.

     oid (+) The user's real organization ID.  (Domain/OS only)

     owd (+) The old working directory,  equivalent  to  the  `-'
             used by cd and pushd.  See also the cwd and dirstack
             shell variables.

     padhour If set, enable  the  printing  of  padding  '0'  for
             hours,  in  24  and 12 hour formats.  E.G.: 07:45:42
             vs. 7:45:42.

             To retain compatibily with  older  versions  numeric
             variables  starting  with  0  are not interpreted as
             octal. Setting this variable  enables  proper  octal

     path    A  list  of  directories  in  which to look for exe-
             cutable commands.  A null word specifies the current
             directory.   If  there is no path variable then only
             full path names will execute.  path is  set  by  the
             shell  at startup from the PATH environment variable
             or, if PATH does not exist,  to  a  system-dependent
             default  something  like  `(/usr/local/bin  /usr/bsd
             /bin /usr/bin .)'.  The shell may put `.'  first  or
             last in path or omit it entirely depending on how it
             was compiled; see the  version  shell  variable.   A
             shell  which  is  given  neither  the  -c nor the -t
             option hashes the contents  of  the  directories  in
             path  after  reading ~/.tcshrc and each time path is
             reset.  If one adds a new command to a directory  in
             path while the shell is active, one may need to do a
             rehash for the shell to find it.

     printexitvalue (+)
             If set and an interactive program exits with a  non-
             zero status, the shell prints `Exit status'.

     prompt  The  string  which  is  printed  before reading each

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             command from the terminal.  prompt may  include  any
             of the following formatting sequences (+), which are
             replaced by the given information:

             %/  The current working directory.
             %~  The current working directory,  but  with  one's
                 home  directory  represented  by  `~'  and other
                 users' home directories represented  by  `~user'
                 as per Filename substitution.  `~user' substitu-
                 tion happens only if the shell has already  used
                 `~user' in a pathname in the current session.
             %c[[0]n], %.[[0]n]
                 The  trailing  component  of the current working
                 directory, or n trailing components if a digit n
                 is  given.   If n begins with `0', the number of
                 skipped components precede the  trailing  compo-
                 nent(s)  in the format `/<skipped>trailing'.  If
                 the ellipsis shell variable is set, skipped com-
                 ponents  are  represented  by an ellipsis so the
                 whole becomes `...trailing'.   `~'  substitution
                 is  done as in `%~' above, but the `~' component
                 is ignored when counting trailing components.
             %C  Like %c, but without `~' substitution.
             %h, %!, !
                 The current history event number.
             %M  The full hostname.
             %m  The hostname up to the first `.'.
             %S (%s)
                 Start (stop) standout mode.
             %B (%b)
                 Start (stop) boldfacing mode.
             %U (%u)
                 Start (stop) underline mode.
             %t, %@
                 The time of day in 12-hour AM/PM format.
             %T  Like `%t', but in 24-hour format  (but  see  the
                 ampm shell variable).
             %p  The  `precise' time of day in 12-hour AM/PM for-
                 mat, with seconds.
             %P  Like `%p', but in 24-hour format  (but  see  the
                 ampm shell variable).
             \c  c is parsed as in bindkey.
             ^c  c is parsed as in bindkey.
             %%  A single `%'.
             %n  The user name.
             %N  The effective user name.
             %j  The number of jobs.
             %d  The weekday in `Day' format.
             %D  The day in `dd' format.
             %w  The month in `Mon' format.
             %W  The month in `mm' format.
             %y  The year in `yy' format.

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             %Y  The year in `yyyy' format.
             %l  The shell's tty.
             %L  Clears  from the end of the prompt to end of the
                 display or the end of the line.
             %$  Expands the shell or environment  variable  name
                 immediately after the `$'.
             %#  `>'  (or  the first character of the promptchars
                 shell variable) for normal users,  `#'  (or  the
                 second  character  of promptchars) for the supe-
                 Includes string as a  literal  escape  sequence.
                 It  should  be  used  only  to  change  terminal
                 attributes and should not move the cursor  loca-
                 tion.   This  cannot  be  the  last  sequence in
             %?  The return code of  the  command  executed  just
                 before the prompt.
             %R  In  prompt2,  the  status  of  the  parser.   In
                 prompt3, the corrected string.  In history,  the
                 history string.

             `%B',  `%S',  `%U' and `%{string%}' are available in
             only eight-bit-clean shells; see the  version  shell

             The bold, standout and underline sequences are often
             used to distinguish a superuser shell.  For example,

                 >  set prompt = "%m [%h] %B[%@]%b [%/] you rang?
                 tut [37] [2:54pm] [/usr/accts/sys] you rang? _

             If `%t', `%@', `%T', `%p', or `%P' is used, and nod-
             ing  is not set, then print `DING!' on the change of
             hour (i.e, `:00'  minutes)  instead  of  the  actual

             Set by default to `%# ' in interactive shells.

     prompt2 (+)
             The string with which to prompt in while and foreach
             loops and after lines ending in `\'.  The same  for-
             mat  sequences may be used as in prompt (q.v.); note
             the variable meaning of `%R'.   Set  by  default  to
             `%R? ' in interactive shells.

     prompt3 (+)
             The  string  with  which  to  prompt when confirming
             automatic  spelling  correction.   The  same  format
             sequences  may be used as in prompt (q.v.); note the
             variable  meaning  of  `%R'.   Set  by  default   to

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User Commands                                             TCSH(1)

             `CORRECT>%R (y|n|e|a)? ' in interactive shells.

     promptchars (+)
             If set (to a two-character string), the `%#' format-
             ting  sequence  in  the  prompt  shell  variable  is
             replaced  with  the first character for normal users
             and the second character for the superuser.

     pushdtohome (+)
             If set, pushd without arguments does `pushd ~', like

     pushdsilent (+)
             If  set,  pushd  and popd do not print the directory

     recexact (+)
             If set, completion completes on an exact match  even
             if a longer match is possible.

     recognize_only_executables (+)
             If  set,  command listing displays only files in the
             path that are executable.  Slow.

     rmstar (+)
             If set, the user is prompted before `rm *'  is  exe-

     rprompt (+)
             The  string  to  print on the right-hand side of the
             screen (after the command input) when the prompt  is
             being displayed on the left.  It recognizes the same
             formatting characters as prompt.  It will  automati-
             cally disappear and reappear as necessary, to ensure
             that command input isn't obscured, and  will  appear
             only  if  the prompt, command input, and itself will
             fit together on the first line.  If edit isn't  set,
             then  rprompt  will  be printed after the prompt and
             before the command input.

     savedirs (+)
             If set, the shell does `dirs -S' before exiting.  If
             the first word is set to a number, at most that many
             directory stack entries are saved.

             If set, the shell does `history -S' before  exiting.
             If  the  first word is set to a number, at most that
             many lines are saved.  (The number must be less than
             or  equal to history.)  If the second word is set to
             `merge', the history list is merged with the  exist-
             ing  history  file instead of replacing it (if there

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             is one) and sorted by time stamp and the most recent
             events are retained.  (+)

     sched (+)
             The format in which the sched builtin command prints
             scheduled events; if not  given,  `%h\t%T\t%R\n'  is
             used.   The  format  sequences  are  described above
             under prompt; note the variable meaning of `%R'.

     shell   The file in which the shell resides.  This  is  used
             in forking shells to interpret files which have exe-
             cute bits set, but which are not executable  by  the
             system.   (See  the  description of Builtin and non-
             builtin  command  execution.)   Initialized  to  the
             (system-dependent) home of the shell.

     shlvl (+)
             The  number  of  nested shells.  Reset to 1 in login
             shells.  See also loginsh.

     status  The status returned by the last command, unless  the
             variable  anyerror  is set, and any error in a pipe-
             line or a backquote  expansion  will  be  propagated
             (this  is  the default csh behavior, and the current
             tcsh default). If  it  terminated  abnormally,  then
             0200 is added to the status.  Builtin commands which
             fail return exit status `1', all other builtin  com-
             mands return status `0'.

     symlinks (+)
             Can  be  set  to several different values to control
             symbolic link (`symlink') resolution:

             If set to `chase', whenever  the  current  directory
             changes  to  a directory containing a symbolic link,
             it is expanded to the real name of the directory  to
             which  the  link points.  This does not work for the
             user's home directory; this is a bug.

             If set to `ignore', the shell tries to  construct  a
             current  directory relative to the current directory
             before the link was crossed.  This means that  cding
             through  a symbolic link and then `cd ..'ing returns
             one to the original directory.   This  affects  only
             builtin commands and filename completion.

             If  set to `expand', the shell tries to fix symbolic
             links by actually  expanding  arguments  which  look
             like path names.  This affects any command, not just
             builtins.  Unfortunately, this  does  not  work  for
             hard-to-recognize  filenames, such as those embedded
             in command options.  Expansion may be  prevented  by

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User Commands                                             TCSH(1)

             quoting.   While  this  setting  is usually the most
             convenient, it is sometimes misleading and sometimes
             confusing  when  it  fails  to recognize an argument
             which should be expanded.  A compromise  is  to  use
             `ignore'  and  use the editor command normalize-path
             (bound by default to ^X-n) when necessary.

             Some examples are in order.   First,  let's  set  up
             some play directories:

                 > cd /tmp
                 > mkdir from from/src to
                 > ln -s from/src to/dst

             Here's the behavior with symlinks unset,

                 > cd /tmp/to/dst; echo $cwd
                 > cd ..; echo $cwd

             here's the behavior with symlinks set to `chase',

                 > cd /tmp/to/dst; echo $cwd
                 > cd ..; echo $cwd

             here's the behavior with symlinks set to `ignore',

                 > cd /tmp/to/dst; echo $cwd
                 > cd ..; echo $cwd

             and   here's  the  behavior  with  symlinks  set  to

                 > cd /tmp/to/dst; echo $cwd
                 > cd ..; echo $cwd
                 > cd /tmp/to/dst; echo $cwd
                 > cd ".."; echo $cwd
                 > /bin/echo ..
                 > /bin/echo ".."

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User Commands                                             TCSH(1)

             Note that `expand'  expansion  1)  works  just  like
             `ignore'  for  builtins  like cd, 2) is prevented by
             quoting, and 3) happens before filenames are  passed
             to non-builtin commands.

     tcsh (+)
             The  version  number  of  the  shell  in  the format
             `R.VV.PP', where `R' is the  major  release  number,
             `VV' the current version and `PP' the patchlevel.

     term    The  terminal  type.   Usually  set  in  ~/.login as
             described under Startup and shutdown.

     time    If set to a number, then  the  time  builtin  (q.v.)
             executes  automatically  after  each  command  which
             takes more than that many CPU seconds.  If there  is
             a second word, it is used as a format string for the
             output of  the  time  builtin.   (u)  The  following
             sequences may be used in the format string:

             %U  The  time  the process spent in user mode in cpu
             %S  The time the process spent in kernel mode in cpu
             %E  The elapsed (wall clock) time in seconds.
             %P  The CPU percentage computed as (%U + %S) / %E.
             %W  Number of times the process was swapped.
             %X  The  average  amount in (shared) text space used
                 in Kbytes.
             %D  The  average  amount  in  (unshared)  data/stack
                 space used in Kbytes.
             %K  The total space used (%X + %D) in Kbytes.
             %M  The maximum memory the process had in use at any
                 time in Kbytes.
             %F  The number of major page faults (page needed  to
                 be brought from disk).
             %R  The number of minor page faults.
             %I  The number of input operations.
             %O  The number of output operations.
             %r  The number of socket messages received.
             %s  The number of socket messages sent.
             %k  The number of signals received.
             %w  The   number   of   voluntary  context  switches
             %c  The number of involuntary context switches.

             Only the first four sequences are supported on  sys-
             tems  without  BSD  resource  limit  functions.  The
             default time format is `%Uu %Ss %E %P %X+%Dk %I+%Oio
             %Fpf+%Ww'  for  systems  that support resource usage
             reporting and `%Uu %Ss %E %P' for  systems  that  do

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User Commands                                             TCSH(1)

             Under Sequent's DYNIX/ptx, %X, %D, %K, %r and %s are
             not  available,   but   the   following   additional
             sequences are:

             %Y  The number of system calls performed.
             %Z  The  number  of  pages  which are zero-filled on
             %i  The number of times  a  process's  resident  set
                 size was increased by the kernel.
             %d  The  number  of  times  a process's resident set
                 size was decreased by the kernel.
             %l  The number of read system calls performed.
             %m  The number of write system calls performed.
             %p  The number of reads from raw disk devices.
             %q  The number of writes to raw disk devices.

             and the default  time  format  is  `%Uu  %Ss  %E  %P
             %I+%Oio %Fpf+%Ww'.  Note that the CPU percentage can
             be higher than 100% on multi-processors.

     tperiod (+)
             The period, in minutes, between  executions  of  the
             periodic special alias.

     tty (+) The  name  of  the  tty, or empty if not attached to

     uid (+) The user's real user ID.

     user    The user's login name.

     verbose If set, causes the  words  of  each  command  to  be
             printed,  after  history substitution (if any).  Set
             by the -v command line option.

     version (+)
             The version ID stamp.  It contains the shell's  ver-
             sion  number  (see tcsh), origin, release date, ven-
             dor,  operating  system  and  machine  (see  VENDOR,
             OSTYPE  and  MACHTYPE) and a comma-separated list of
             options which were set  at  compile  time.   Options
             which  are  set  by  default in the distribution are

             8b    The shell is eight bit clean; default
             7b    The shell is not eight bit clean
             wide  The shell is multibyte  encoding  clean  (like
             nls   The  system's NLS is used; default for systems
                   with NLS
             lf    Login  shells   execute   /etc/.login   before
                   instead  of  after  /etc/.cshrc  and  ~/.login

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User Commands                                             TCSH(1)

                   before instead of after ~/.tcshrc and  ~/.his-
             dl    `.' is put last in path for security; default
             nd    `.' is omitted from path for security
             vi    vi-style  editing  is  the default rather than
             dtr   Login shells drop DTR when exiting
             bye   bye is a synonym for  logout  and  log  is  an
                   alternate name for watchlog
             al    autologout is enabled; default
             kan   Kanji  is  used  if  appropriate  according to
                   locale  settings,  unless  the  nokanji  shell
                   variable is set
             sm    The system's malloc(3C) is used
             hb    The  `#!<program>  <args>'  convention is emu-
                   lated when executing shell scripts
             ng    The newgrp builtin is available
             rh    The shell attempts to set the REMOTEHOST envi-
                   ronment variable
             afs   The shell verifies your password with the ker-
                   beros server if  local  authentication  fails.
                   The  afsuser  shell  variable  or  the AFSUSER
                   environment variable override your local user-
                   name if set.

             An  administrator  may  enter  additional strings to
             indicate differences in the local version.

     visiblebell (+)
             If set, a screen flash is used rather than the audi-
             ble bell.  See also nobeep.

     watch (+)
             A  list  of  user/terminal pairs to watch for logins
             and logouts.  If either the user is `any' all termi-
             nals  are watched for the given user and vice versa.
             Setting watch to `(any any)' watches all  users  and
             terminals.  For example,

                 set watch = (george ttyd1 any console $user any)

             reports activity of the user `george' on ttyd1,  any
             user  on  the console, and oneself (or a trespasser)
             on any terminal.

             Logins and logouts are checked every 10  minutes  by
             default, but the first word of watch can be set to a
             number to check every so many minutes.  For example,

                 set watch = (1 any any)

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User Commands                                             TCSH(1)

             reports any login/logout once every minute.  For the
             impatient, the log builtin command triggers a  watch
             report at any time.  All current logins are reported
             (as with the log builtin) when watch is first set.

             The who shell variable controls the format of  watch

     who (+) The format string for watch messages.  The following
             sequences are replaced by the given information:

             %n  The name of the user who logged in/out.
             %a  The observed action, i.e., `logged on',  `logged
                 off' or `replaced olduser on'.
             %l  The  terminal  (tty)  on  which  the user logged
             %M  The full hostname of the remote host, or `local'
                 if the login/logout was from the local host.
             %m  The  hostname of the remote host up to the first
                 `.'.  The full name is printed if it  is  an  IP
                 address or an X Window System display.

             %M  and  %m are available on only systems that store
             the remote hostname in /etc/utmp or /etc/utmpx.   If
             unset,  `%n  has %a %l from %m.' is used, or `%n has
             %a %l.' on systems  which  don't  store  the  remote

     wordchars (+)
             A  list of non-alphanumeric characters to be consid-
             ered part of a word by the  forward-word,  backward-
             word  etc.,  editor commands.  If unset, `*?_-.[]~='
             is used.

     AFSUSER (+)
             Equivalent to the afsuser shell variable.

     COLUMNS The number of columns in the terminal.  See Terminal

     DISPLAY Used  by  X  Window  System (see X(5)).  If set, the
             shell does not set autologout (q.v.).

     EDITOR  The pathname to a  default  editor.   See  also  the
             VISUAL  environment  variable  and the run-fg-editor
             editor command.

     GROUP (+)
             Equivalent to the group shell variable.

     HOME    Equivalent to the home shell variable.

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User Commands                                             TCSH(1)

     HOST (+)
             Initialized to the name of the machine on which  the
             shell  is  running,  as  determined  by the gethost-
             name(3C) library call.

     HOSTTYPE (+)
             Initialized to the type  of  machine  on  which  the
             shell  is  running,  as  determined at compile time.
             This variable is obsolete and will be removed  in  a
             future version.

     HPATH (+)
             A  colon-separated  list of directories in which the
             run-help editor command looks for command documenta-

     LANG    Gives  the  preferred  character  environment.   See
             Native Language System support.

             If set, only ctype character  handling  is  changed.
             See Native Language System support.

     LINES   The  number  of lines in the terminal.  See Terminal

             The format of this variable is  reminiscent  of  the
             termcap(5)  file  format;  a colon-separated list of
             expressions of the form "xx=string", where "xx" is a
             two-character  variable  name.   The  variables with
             their associated defaults are:

                 no   0      Normal (non-filename) text
                 fi   0      Regular file
                 di   01;34  Directory
                 ln   01;36  Symbolic link
                 pi   33     Named pipe (FIFO)
                 so   01;35  Socket
                 do   01;35  Door
                 bd   01;33  Block device
                 cd   01;32  Character device
                 ex   01;32  Executable file
                 mi   (none) Missing file (defaults to fi)
                 or   (none) Orphaned symbolic link (defaults  to
                 lc   ^[[    Left code
                 rc   m      Right code
                 ec   (none) End code (replaces lc+no+rc)

             You  need  to include only the variables you want to
             change from the default.

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User Commands                                             TCSH(1)

             File names can also be colorized based  on  filename
             extension.  This is specified in the LS_COLORS vari-
             able using the syntax "*ext=string".   For  example,
             using ISO 6429 codes, to color all C-language source
             files blue you would specify "*.c=34".   This  would
             color all files ending in .c in blue (34) color.

             Control   characters   can   be  written  either  in
             C-style-escaped notation, or  in  stty-like  ^-nota-
             tion.   The  C-style  notation adds ^[ for Escape, _
             for a normal space character, and ? for Delete.   In
             addition,  the  ^[  escape  character can be used to
             override the default interpretation of ^[, ^, :  and

             Each  file will be written as <lc> <color-code> <rc>
             <filename> <ec>.  If the <ec> code is undefined, the
             sequence  <lc> <no> <rc> will be used instead.  This
             is generally more convenient to use, but  less  gen-
             eral.  The left, right and end codes are provided so
             you don't have to type common parts  over  and  over
             again  and to support weird terminals; you will gen-
             erally not need to change them at  all  unless  your
             terminal does not use ISO 6429 color sequences but a
             different system.

             If your terminal does use ISO 6429 color codes,  you
             can compose the type codes (i.e., all except the lc,
             rc, and ec codes) from numerical commands  separated
             by semicolons.  The most common commands are:

                     0   to restore default color
                     1   for brighter colors
                     4   for underlined text
                     5   for flashing text
                     30  for black foreground
                     31  for red foreground
                     32  for green foreground
                     33  for yellow (or brown) foreground
                     34  for blue foreground
                     35  for purple foreground
                     36  for cyan foreground
                     37  for white (or gray) foreground
                     40  for black background
                     41  for red background
                     42  for green background
                     43  for yellow (or brown) background
                     44  for blue background
                     45  for purple background
                     46  for cyan background
                     47  for white (or gray) background

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User Commands                                             TCSH(1)

             Not all commands will work on all systems or display

             A few terminal programs do not recognize the default
             end code properly.  If all text gets colorized after
             you do a directory listing, try changing the no  and
             fi  codes  from  0  to  the numerical codes for your
             standard fore- and background colors.

     MACHTYPE (+)
             The machine type (microprocessor  class  or  machine
             model), as determined at compile time.

     NOREBIND (+)
             If  set,  printable  characters  are  not rebound to
             self-insert-command.   See  Native  Language  System

     OSTYPE (+)
             The operating system, as determined at compile time.

     PATH    A colon-separated list of directories  in  which  to
             look  for executables.  Equivalent to the path shell
             variable, but in a different format.

     PWD (+) Equivalent to the cwd shell variable, but  not  syn-
             chronized to it; updated only after an actual direc-
             tory change.

             The host from which the user has logged in remotely,
             if  this is the case and the shell is able to deter-
             mine it.  Set only if the shell was so compiled; see
             the version shell variable.

     SHLVL (+)
             Equivalent to the shlvl shell variable.

     SYSTYPE (+)
             The current system type.  (Domain/OS only)

     TERM    Equivalent to the term shell variable.

     TERMCAP The  terminal  capability string.  See Terminal man-

     USER    Equivalent to the user shell variable.

     VENDOR (+)
             The vendor, as determined at compile time.

     VISUAL  The pathname to a default full-screen  editor.   See

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User Commands                                             TCSH(1)

             also the EDITOR environment variable and the run-fg-
             editor editor command.

     /etc/csh.cshrc  Read first by every shell.  ConvexOS,  Stel-
                     lix  and  Intel use /etc/cshrc and NeXTs use
                     /etc/cshrc.std.  A/UX, AMIX, Cray  and  IRIX
                     have  no equivalent in csh(1), but read this
                     file in tcsh anyway.  Solaris does not  have
                     it either, but tcsh reads /etc/.cshrc.  (+)
     /etc/csh.login  Read  by  login shells after /etc/csh.cshrc.
                     ConvexOS, Stellix and Intel use  /etc/login,
                     NeXTs   use   /etc/login.std,  Solaris  uses
                     /etc/.login and A/UX, AMIX,  Cray  and  IRIX
                     use /etc/cshrc.
     ~/.tcshrc (+)   Read  by every shell after /etc/csh.cshrc or
                     its equivalent.
     ~/.cshrc        Read by every shell,  if  ~/.tcshrc  doesn't
                     exist,  after  /etc/csh.cshrc or its equiva-
                     lent.  This manual uses `~/.tcshrc' to  mean
                     `~/.tcshrc  or,  if  ~/.tcshrc is not found,
     ~/.history      Read by  login  shells  after  ~/.tcshrc  if
                     savehist is set, but see also histfile.
     ~/.login        Read  by  login  shells  after  ~/.tcshrc or
                     ~/.history.  The shell may  be  compiled  to
                     read   ~/.login   before  instead  of  after
                     ~/.tcshrc and ~/.history;  see  the  version
                     shell variable.
     ~/.cshdirs (+)  Read  by  login  shells  after  ~/.login  if
                     savedirs is set, but see also dirsfile.
     /etc/csh.logout Read by login shells at  logout.   ConvexOS,
                     Stellix  and Intel use /etc/logout and NeXTs
                     use /etc/logout.std.  A/UX, AMIX,  Cray  and
                     IRIX  have no equivalent in csh(1), but read
                     this file in tcsh anyway.  Solaris 2.x  does
                     not   have   it   either,   but  tcsh  reads
                     /etc/.logout.  (+)
     ~/.logout       Read  by  login  shells  at   logout   after
                     /etc/csh.logout or its equivalent.
     /bin/sh         Used to interpret shell scripts not starting
                     with a `#'.
     /tmp/sh*        Temporary file for `<<'.
     /etc/passwd     Source of home directories for `~name'  sub-

     The  order in which startup files are read may differ if the
     shell was so compiled; see Startup and shutdown and the ver-
     sion shell variable.

     This   manual   describes  tcsh  as  a  single  entity,  but

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User Commands                                             TCSH(1)

     experienced csh(1) users will want to pay special  attention
     to tcsh's new features.

     A   command-line   editor,   which  supports  GNU  Emacs  or
     vi(1)-style key bindings.  See The command-line  editor  and
     Editor commands.

     Programmable,  interactive word completion and listing.  See
     Completion and  listing  and  the  complete  and  uncomplete
     builtin commands.

     Spelling  correction (q.v.) of filenames, commands and vari-

     Editor commands (q.v.) which perform other useful  functions
     in  the  middle  of  typed commands, including documentation
     lookup (run-help), quick editor  restarting  (run-fg-editor)
     and command resolution (which-command).

     An  enhanced  history mechanism.  Events in the history list
     are time-stamped.  See also  the  history  command  and  its
     associated  shell variables, the previously undocumented `#'
     event specifier and new modifiers  under  History  substitu-
     tion,   the  *-history,  history-search-*,  i-search-*,  vi-
     search-* and toggle-literal-history editor commands and  the
     histlit shell variable.

     Enhanced  directory  parsing  and  directory stack handling.
     See the cd, pushd, popd and dirs commands and their  associ-
     ated  shell  variables,  the  description of Directory stack
     substitution, the dirstack, owd and symlinks shell variables
     and  the  normalize-command  and  normalize-path editor com-

     Negation in glob-patterns.  See Filename substitution.

     New File inquiry operators (q.v.)  and  a  filetest  builtin
     which uses them.

     A  variety  of  Automatic,  periodic and timed events (q.v.)
     including  scheduled  events,  special  aliases,   automatic
     logout and terminal locking, command timing and watching for
     logins and logouts.

     Support for the Native Language System (see Native  Language
     System support), OS variant features (see OS variant support
     and the echo_style shell variable) and system-dependent file
     locations (see FILES).

     Extensive  terminal-management  capabilities.   See Terminal

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User Commands                                             TCSH(1)

     New builtin commands including builtins, hup, ls-F,  newgrp,
     printenv, which and where (q.v.).

     New  variables that make useful information easily available
     to the shell.  See the gid, loginsh, oid, shlvl, tcsh,  tty,
     uid  and  version  shell variables and the HOST, REMOTEHOST,
     VENDOR, OSTYPE and MACHTYPE environment variables.

     A new syntax for including useful information in the  prompt
     string  (see  prompt),  and  special  prompts  for loops and
     spelling correction (see prompt2 and prompt3).

     Read-only variables.  See Variable substitution.

     When a suspended command is restarted, the shell prints  the
     directory  it  started in if this is different from the cur-
     rent directory.  This can be misleading (i.e., wrong) as the
     job may have changed directories internally.

     Shell builtin functions are not stoppable/restartable.  Com-
     mand sequences of the form `a ; b ; c' are also not  handled
     gracefully  when stopping is attempted.  If you suspend `b',
     the shell will then immediately execute `c'.  This is  espe-
     cially  noticeable  if this expansion results from an alias.
     It suffices to place the sequence of  commands  in  ()'s  to
     force it to a subshell, i.e., `( a ; b ; c )'.

     Control over tty output after processes are started is prim-
     itive; perhaps this will inspire someone to work on  a  good
     virtual terminal interface.  In a virtual terminal interface
     much more interesting things could be done with output  con-

     Alias  substitution  is most often used to clumsily simulate
     shell procedures; shell procedures should be provided rather
     than aliases.

     Control structures should be parsed rather than being recog-
     nized as built-in commands.  This would allow  control  com-
     mands to be placed anywhere, to be combined with `|', and to
     be used with `&' and `;' metasyntax.

     foreach doesn't ignore here documents when looking  for  its

     It should be possible to use the `:' modifiers on the output
     of command substitutions.

     The screen update for lines longer than the screen width  is
     very  poor  if the terminal cannot move the cursor up (i.e.,
     terminal type `dumb').

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User Commands                                             TCSH(1)

     HPATH and NOREBIND don't need to be environment variables.

     Glob-patterns which do not use `?', `*' or `[]' or which use
     `{}' or `~' are not negated correctly.

     The  single-command  form of if does output redirection even
     if the expression is false and the command is not  executed.

     ls-F  includes  file  identification characters when sorting
     filenames and does not handle control  characters  in  file-
     names well.  It cannot be interrupted.

     Command  substitution  supports multiple commands and condi-
     tions, but not cycles or backward gotos.

     Report bugs at, preferably  with  fixes.
     If  you  want  to  help maintain and test tcsh, send mail to with the text `subscribe tcsh'  on  a
     line by itself in the body.

     In 1964, DEC produced the PDP-6.  The PDP-10 was a later re-
     implementation.  It was re-christened  the  DECsystem-10  in
     1970  or so when DEC brought out the second model, the KI10.

     TENEX was created at Bolt, Beranek &  Newman  (a  Cambridge,
     Massachusetts  think  tank)  in  1972  as  an  experiment in
     demand-paged virtual memory operating systems.  They built a
     new  pager  for the DEC PDP-10 and created the OS to go with
     it.  It was extremely successful in academia.

     In 1975, DEC brought out a new  model  of  the  PDP-10,  the
     KL10;  they  intended to have only a version of TENEX, which
     they had licensed from BBN, for the new  box.   They  called
     their version TOPS-20 (their capitalization is trademarked).
     A lot of TOPS-10 users (`The OPerating System  for  PDP-10')
     objected; thus DEC found themselves supporting two incompat-
     ible systems on the same hardware--but then there were 6  on
     the PDP-11!

     TENEX,  and TOPS-20 to version 3, had command completion via
     a user-code-level subroutine library  called  ULTCMD.   With
     version  3,  DEC moved all that capability and more into the
     monitor (`kernel' for  you  Unix  types),  accessed  by  the
     COMND%  JSYS  (`Jump  to SYStem' instruction, the supervisor
     call mechanism [are my IBM roots also showing?]).

     The creator of tcsh was impressed by this feature  and  sev-
     eral  others  of TENEX and TOPS-20, and created a version of
     csh which mimicked them.

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User Commands                                             TCSH(1)

     The system limits argument lists to ARG_MAX characters.

     The number of arguments to a command which involves filename
     expansion  is  limited  to  1/6th  the  number of characters
     allowed in an argument list.

     Command substitutions may substitute no more characters than
     are allowed in an argument list.

     To  detect  looping, the shell restricts the number of alias
     substitutions on a single line to 20.

     See  attributes(5)  for  descriptions   of   the   following

     |Availability   | shell/tcsh       |
     |Stability      | Volatile         |
     csh(1),  emacs(1), ls(1), newgrp(1), sh(1), stty(1), su(1M),
     tset(1B),  vi(1),  X(5),  access(2),   execve(2),   fork(2),
     killpg(3C),  pipe(2),  setrlimit(2),  sigvec(3UCB), stat(2),
     umask(2),  vfork(2),  wait(2),  malloc(3C),   setlocale(3C),
     tty(7D),   a.out(4),  terminfo(4),  environ(5),  termio(7I),
     Introduction to the C Shell

     This manual documents tcsh 6.18.01 (Astron) 2012-02-14.

     William Joy
       Original author of csh(1)
     J.E. Kulp, IIASA, Laxenburg, Austria
       Job control and directory stack features
     Ken Greer, HP Labs, 1981
       File name completion
     Mike Ellis, Fairchild, 1983
       Command name recognition/completion
     Paul Placeway, Ohio State CIS Dept., 1983-1993
       Command line editor, prompt routines, new glob syntax  and
       numerous fixes and speedups
     Karl Kleinpaste, CCI 1983-4
       Special   aliases,   directory   stack  extraction  stuff,
       login/logout watch, scheduled events, and the idea of  the
       new prompt format

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User Commands                                             TCSH(1)

     Rayan Zachariassen, University of Toronto, 1984
       ls-F  and which builtins and numerous bug fixes, modifica-
       tions and speedups
     Chris Kingsley, Caltech
       Fast storage allocator routines
     Chris Grevstad, TRW, 1987
       Incorporated 4.3BSD csh into tcsh
     Christos S. Zoulas, Cornell U. EE Dept., 1987-94
       Ports to HPUX, SVR2 and SVR3, a SysV version  of  getwd.c,
       SHORT_STRINGS support and a new version of sh.glob.c
     James J Dempsey, BBN, and Paul Placeway, OSU, 1988
       A/UX port
     Daniel Long, NNSC, 1988
     Patrick Wolfe, Kuck and Associates, Inc., 1988
       vi mode cleanup
     David C Lawrence, Rensselaer Polytechnic Institute, 1989
       autolist and ambiguous completion listing
     Alec Wolman, DEC, 1989
       Newlines in the prompt
     Matt Landau, BBN, 1989
     Ray Moody, Purdue Physics, 1989
       Magic space bar history expansion
     Mordechai ????, Intel, 1989
       printprompt() fixes and additions
     Kazuhiro Honda, Dept. of Computer Science, Keio University,
       Automatic spelling correction and prompt3
     Per Hedeland, Ellemtel, Sweden, 1990-
       Various bugfixes, improvements and manual updates
     Hans J. Albertsson (Sun Sweden)
       ampm, settc and telltc
     Michael Bloom
       Interrupt handling fixes
     Michael Fine, Digital Equipment Corp
       Extended key support
     Eric Schnoebelen, Convex, 1990
       Convex support, lots of csh bug fixes, save and restore of
       directory stack
     Ron Flax, Apple, 1990
       A/UX 2.0 (re)port
     Dan Oscarsson, LTH Sweden, 1990
       NLS  support  and simulated NLS support for non NLS sites,
     Johan Widen, SICS Sweden, 1990
       shlvl, Mach support, correct-line, 8-bit printing
     Matt Day, Sanyo Icon, 1990
       POSIX termio support, SysV limit fixes
     Jaap Vermeulen, Sequent, 1990-91
       Vi mode fixes, expand-line, window change fixes,  Symmetry

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User Commands                                             TCSH(1)

     Martin Boyer, Institut de recherche d'Hydro-Quebec, 1991
       autolist  beeping  options, modified the history search to
       search for the whole string from the beginning of the line
       to the cursor.
     Scott Krotz, Motorola, 1991
       Minix port
     David Dawes, Sydney U. Australia, Physics Dept., 1991
       SVR4 job control fixes
     Jose Sousa, Interactive Systems Corp., 1991
       Extended vi fixes and vi delete command
     Marc Horowitz, MIT, 1991
       ANSIfication  fixes,  new  exec hashing code, imake fixes,
     Bruce Sterling Woodcock,, 1991-1995
       ETA and Pyramid port, Makefile and lint fixes, ignoreeof=n
       addition,  and  various  other portability changes and bug
     Jeff Fink, 1992
       complete-word-fwd and complete-word-back
     Harry C. Pulley, 1992
       Coherent port
     Andy Phillips, Mullard Space Science Lab U.K., 1992
       VMS-POSIX port
     Beto Appleton, IBM Corp., 1992
       Walking process group fixes, csh  bug  fixes,  POSIX  file
       tests, POSIX SIGHUP
     Scott Bolte, Cray Computer Corp., 1992
       CSOS port
     Kaveh R. Ghazi, Rutgers University, 1992
       Tek,  m88k,  Titan  and  Masscomp  ports and fixes.  Added
       autoconf support.
     Mark Linderman, Cornell University, 1992
       OS/2 port
     Mika Liljeberg, liljeber@kruuna.Helsinki.FI, 1992
       Linux port
     Tim P. Starrin, NASA Langley Research Center Operations,
       Read-only variables
     Dave Schweisguth, Yale University, 1993-4
       New man page and tcsh.man2html
     Larry Schwimmer, Stanford University, 1993
       AFS and HESIOD patches
     Luke Mewburn, RMIT University, 1994-6
       Enhanced  directory printing in prompt, added ellipsis and
     Edward Hutchins, Silicon Graphics Inc., 1996
       Added implicit cd.
     Martin Kraemer, 1997
       Ported to Siemens Nixdorf EBCDIC machine
     Amol Deshpande, Microsoft, 1997
       Ported to WIN32 (Windows/95 and Windows/NT); wrote all the
       missing  library  and message catalog code to interface to

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User Commands                                             TCSH(1)

     Taga Nayuta, 1998
       Color ls additions.

     Bryan Dunlap, Clayton Elwell, Karl Kleinpaste,  Bob  Manson,
     Steve  Romig,  Diana Smetters, Bob Sutterfield, Mark Verber,
     Elizabeth Zwicky and all the other people at Ohio State  for
     suggestions and encouragement

     All  the  people  on the net, for putting up with, reporting
     bugs in, and suggesting new additions to each and every ver-

     Richard M. Alderson III, for writing the `T in tcsh' section

     It is no longer possible for variables to have a  '-'  or  a
     '='  within the name. Any variables of this form will gener-
     ate a 'setenv: Syntax error' error message.

     This  software  was   built   from   source   available   at    The  original
     community       source       was       downloaded       from

     Further  information about this software can be found on the
     open source community website at

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