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man pages section 3: Extended Library Functions, Volume 1

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Updated: Wednesday, July 27, 2022
 
 

c (3erl)

Name

c - Command interface module.

Synopsis

Please see following description for synopsis

Description

c(3)                       Erlang Module Definition                       c(3)



NAME
       c - Command interface module.

DESCRIPTION
       This module enables users to enter the short form of some commonly used
       commands.

   Note:
       These functions are intended for interactive use in  the  Erlang  shell
       only. The module prefix can be omitted.


EXPORTS
       bt(Pid) -> ok | undefined

              Types:

                 Pid = pid()

              Stack backtrace for a process. Equivalent to erlang:process_dis-
              play(Pid, backtrace).

       c(Module) -> {ok, ModuleName} | error

              Types:

                 Module = file:name()
                 ModuleName = module()

              Works like c(Module, []).

       c(Module, Options) -> {ok, ModuleName} | error

              Types:

                 Module = file:name()
                 Options = [compile:option()] | compile:option()
                 ModuleName = module()

              Compiles and then purges and loads the code for a module. Module
              can be either a module name or a source file path, with or with-
              out .erl extension.

              If Module is a string, it is assumed to be a source  file  path,
              and  the  compiler  will attempt to compile the source file with
              the options Options. If compilation fails, the old  object  file
              (if any) is deleted.

              If Module is an atom, a source file with that exact name or with
              .erl extension will be looked for. If found, the source file  is
              compiled with the options Options. If compilation fails, the old
              object file (if any) is deleted.

              If Module is an atom and is not the path of a source file,  then
              the code path is searched to locate the object file for the mod-
              ule and extract its original compiler options and  source  path.
              If  the  source  file  is  not  found  in the original location,
              filelib:find_source/1 is used to search for it relative  to  the
              directory of the object file.

              The  source  file  is  compiled  with  the  the original options
              appended to the given Options,  the  output  replacing  the  old
              object file if and only if compilation succeeds.

              Notice  that purging the code means that any processes lingering
              in old code for the module are killed without warning. For  more
              information, see the code module.

       c(Module, Options, Filter) -> {ok, ModuleName} | error

              Types:

                 Module = atom()
                 Options = [compile:option()]
                 Filter = fun((compile:option()) -> boolean())
                 ModuleName = module()

              Compiles  and  then purges and loads the code for module Module,
              which must be an atom.

              The code path is searched to locate the object file  for  module
              Module  and  extract  its  original  compiler options and source
              path. If the source file is not found in the original  location,
              filelib:find_source/1  is  used to search for it relative to the
              directory of the object file.

              The source file  is  compiled  with  the  the  original  options
              appended  to  the  given  Options,  the output replacing the old
              object file if and only if compilation  succeeds.  The  function
              Filter specifies which elements to remove from the original com-
              piler options before the new options are added. The  Filter  fun
              should return true for options to keep, and false for options to
              remove.

              Notice that purging the code means that any processes  lingering
              in  old code for the module are killed without warning. For more
              information, see the code module.

       cd(Dir) -> ok

              Types:

                 Dir = file:name()

              Changes working directory to Dir, which can be a relative  name,
              and then prints the name of the new working directory.

              Example:

              2> cd("../erlang").
              /home/ron/erlang

       erlangrc(PathList) -> {ok, file:filename()} | {error, term()}

              Types:

                 PathList = [Dir :: file:name()]

              Search PathList and load .erlang resource file if found.

       flush() -> ok

              Flushes any messages sent to the shell.

       help() -> ok

              Displays  help  information:  all valid shell internal commands,
              and commands in this module.

       h(Module :: module()) -> h_return()

              Types:

                 h_return() =
                     ok | {error, missing | {unknown_format, unicode:chardata()}}

              Print the documentation for Module

       h(Module :: module(), Function :: function()) -> hf_return()

              Types:

                 h_return() =
                     ok | {error, missing | {unknown_format, unicode:chardata()}}
                 hf_return() = h_return() | {error, function_missing}

              Print the documentation for all Module:Functions (regardless  of
              arity).

       h(Module :: module(), Function :: function(), Arity :: arity()) ->
            hf_return()

              Types:

                 h_return() =
                     ok | {error, missing | {unknown_format, unicode:chardata()}}
                 hf_return() = h_return() | {error, function_missing}

              Print the documentation for Module:Function/Arity.

       ht(Module :: module()) -> h_return()

              Types:

                 h_return() =
                     ok | {error, missing | {unknown_format, unicode:chardata()}}

              Print the type documentation for Module

       ht(Module :: module(), Type :: atom()) -> ht_return()

              Types:

                 h_return() =
                     ok | {error, missing | {unknown_format, unicode:chardata()}}
                 ht_return() = h_return() | {error, type_missing}

              Print  the  type  documentation for Type in Module regardless of
              arity.

       ht(Module :: module(), Type :: atom(), Arity :: arity()) ->
             ht_return()

              Types:

                 h_return() =
                     ok | {error, missing | {unknown_format, unicode:chardata()}}
                 ht_return() = h_return() | {error, type_missing}

              Print the type documentation for Type/Arity in Module.

       i() -> ok

       ni() -> ok

              i/0 displays system information, listing information  about  all
              processes. ni/0 does the same, but for all nodes the network.

       i(X, Y, Z) -> [{atom(), term()}]

              Types:

                 X = Y = Z = integer() >= 0

              Displays    information   about   a   process,   Equivalent   to
              process_info(pid(X, Y, Z)), but location transparent.

       l(Module) -> code:load_ret()

              Types:

                 Module = module()

              Purges  and   loads,   or   reloads,   a   module   by   calling
              code:purge(Module) followed by code:load_file(Module).

              Notice  that purging the code means that any processes lingering
              in old code for the module are killed without warning. For  more
              information, see code/3.

       lc(Files) -> ok

              Types:

                 Files = [File]
                 File

              Compiles   a   list   of  files  by  calling  compile:file(File,
              [report_errors, report_warnings]) for each File in Files.

              For information about File, see file:filename().

       lm() -> [code:load_ret()]

              Reloads all currently loaded modules that have changed  on  disk
              (see  mm()).  Returns  the list of results from calling l(M) for
              each such M.

       ls() -> ok

              Lists files in the current directory.

       ls(Dir) -> ok

              Types:

                 Dir = file:name()

              Lists files in directory Dir or, if Dir is a  file,  only  lists
              it.

       m() -> ok

              Displays  information  about  the  loaded modules, including the
              files from which they have been loaded.

       m(Module) -> ok

              Types:

                 Module = module()

              Displays information about Module.

       mm() -> [module()]

              Lists all modified  modules.  Shorthand  for  code:modified_mod-
              ules/0.

       memory() -> [{Type, Size}]

              Types:

                 Type = atom()
                 Size = integer() >= 0

              Memory allocation information. Equivalent to erlang:memory/0.

       memory(Type) -> Size

       memory(Types) -> [{Type, Size}]

              Types:

                 Types = [Type]
                 Type = atom()
                 Size = integer() >= 0

              Memory allocation information. Equivalent to erlang:memory/1.

       nc(File) -> {ok, Module} | error

       nc(File, Options) -> {ok, Module} | error

              Types:

                 File = file:name()
                 Options = [Option] | Option
                 Option = compile:option()
                 Module = module()

              Compiles  and  then  loads  the  code  for  a file on all nodes.
              Options defaults to []. Compilation is equivalent to:

              compile:file(File, Options ++ [report_errors, report_warnings])

       nl(Module) -> abcast | error

              Types:

                 Module = module()

              Loads Module on all nodes.

       pid(X, Y, Z) -> pid()

              Types:

                 X = Y = Z = integer() >= 0

              Converts X, Y, Z to pid <X.Y.Z>. This function  is  only  to  be
              used when debugging.

       pwd() -> ok

              Prints the name of the working directory.

       q() -> no_return()

              This  function  is shorthand for init:stop(), that is, it causes
              the node to stop in a controlled fashion.

       regs() -> ok

       nregs() -> ok

              regs/0 displays  information  about  all  registered  processes.
              nregs/0 does the same, but for all nodes in the network.

       uptime() -> ok

              Prints   the   node   uptime  (as  specified  by  erlang:statis-
              tics(wall_clock)) in human-readable form.

       xm(ModSpec) -> void()

              Types:

                 ModSpec = Module | Filename
                  Module = atom()
                  Filename = string()

              Finds undefined functions, unused functions, and calls to depre-
              cated functions in a module by calling xref:m/1.

       y(File) -> YeccRet

              Types:

                 File = name()
                 YeccRet

              Generates an LALR-1 parser. Equivalent to:

              yecc:file(File)

              For information about File = name(), see filename(3). For infor-
              mation about YeccRet, see yecc:file/2.

       y(File, Options) -> YeccRet

              Types:

                 File = name()
                 Options, YeccRet

              Generates an LALR-1 parser. Equivalent to:

              yecc:file(File, Options)

              For information about File = name(), see filename(3). For infor-
              mation about Options and YeccRet, see yecc:file/2.

SEE ALSO
       filename(3), compile(3), erlang(3), yecc(3), xref(3)



Ericsson AB                       stdlib 3.17                             c(3)