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Complete::Tcsh - Completion module for tcsh shell


This document describes version 0.030 of Complete::Tcsh (from Perl distribution Complete-Tcsh), released on 2019-12-20.


tcsh allows completion to come from various sources. One of the simplest is from a list of words:

 % complete CMDNAME 'p/*/(one two three)/'

Another source is from an external command:

 % complete CMDNAME 'p/*/`mycompleter --somearg`/'

The command receives one environment variables COMMAND_LINE (string, raw command-line). Unlike bash, tcsh does not (yet) provide something akin to COMP_POINT in bash. Command is expected to print completion entries, one line at a time.

 % cat foo-complete
 use Complete::Tcsh qw(parse_cmdline format_completion);
 use Complete::Util qw(complete_array_elem);
 my ($words, $cword) = @{ parse_cmdline() };
 my $res = complete_array_elem(array=>[qw/--help --verbose --version/], word=>$words->[$cword]);
 print format_completion($res);

 % complete foo 'p/*/`foo-complete`/'
 % foo --v<Tab>
 --verbose --version

This module provides routines for you to be doing the above.

Also, unlike bash, currently tcsh does not allow delegating completion to a shell function.




 format_completion($completion) -> str|array

Format completion for output (for shell).

tcsh accepts completion reply in the form of one entry per line to STDOUT. Currently the formatting is done using Complete::Bash's format_completion because escaping rule and so on are not yet well defined in tcsh.

This function is not exported by default, but exportable.

Arguments ('*' denotes required arguments):

  • $completion* => hash|array

    Completion answer structure.

    Either an array or hash, as described in Complete.

Return value: Formatted string (or array, if `as` is set to `array`) (str|array)



 parse_cmdline($cmdline) -> array

Parse shell command-line for processing by completion routines.

This function converts COMMAND_LINE (str) given by tcsh to become something like COMP_WORDS (array) and COMP_CWORD (int), like what bash supplies to shell functions. Currently implemented using Complete::Bash's parse_cmdline.

This function is not exported by default, but exportable.

Arguments ('*' denotes required arguments):

  • $cmdline => str

    Command-line, defaults to COMMAND_LINE environment.

Return value: (array)

Return a 2-element array: [$words, $cword]. $words is array of str, equivalent to COMP_WORDS provided by bash to shell functions. $cword is an integer, equivalent to COMP_CWORD provided by bash to shell functions. The word to be completed is at $words->[$cword].

Note that COMP_LINE includes the command name. If you want the command-line arguments only (like in @ARGV), you need to strip the first element from $words and reduce $cword by 1.


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Source repository is at


Please report any bugs or feature requests on the bugtracker website

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.




tcsh manual.


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This software is copyright (c) 2019, 2015, 2014 by

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.