NAME

File::Symlink::Util - Utilities related to symbolic links

VERSION

This document describes version 0.005 of File::Symlink::Util (from Perl distribution File-Symlink-Util), released on 2023-08-25.

SYNOPSIS

 use File::Symlink::Util qw(
                       symlink_rel
                       symlink_abs
                       adjust_rel_symlink
                       check_symlink
 );

 chdir "/home/ujang";

 # create a relative path symlink
 symlink_rel "/etc/passwd", "symlink1";      # symlink1 -> ../../etc/passwd
 symlink_rel "../../etc/passwd", "symlink1"; # symlink1 -> ../../etc/passwd

 # create an absolute path symlink
 symlink_abs "/etc/passwd", "symlink1";      # symlink1 -> ../../etc/passwd
 symlink_abs "../../etc/passwd", "symlink1"; # symlink1 -> ../../etc/passwd

 # adjust second symlink to be relative to the second path
 symlink "dir1/target", "symlink1";
 % cp -a  "symlink1", "dir2/symlink2";           # dir2/symlink2 points to dir1/target, which is now broken
 adjust_rel_symlink "symlink1", "dir2/symlink2"; # dir2/symlink2 is now fixed, points to ../dir1/target

 # check various aspects of a symlink
 my $res = check_symlink(symlink => "symlink1");                                     # => [200, "OK", []]
 my $res = check_symlink(symlink => "not-a-symlink");                                # => [500, "Errors", ["File is not a symlink"]]
 my $res = check_symlink(symlink => "link-to-a-pic.txt", is_abs=>1, ext_matches=>1); # => [500, "Errors", ["Symlink target is not absolute path", "Extension of symlink does not match target's (jpg)"]]

DESCRIPTION

FUNCTIONS

symlink_rel

Usage:

 symlink_rel($dest_path, $link_path);

Create a relative path symlink. Basically perform File::Spec->abs2rel($dest_path) before symlink().

symlink_abs

Usage:

 symlink_rel($dest_path, $link_path);

Create an absolute path symlink. Basically perform File::Spec->rel2abs($dest_path) before symlink().

adjust_rel_symlink

Usage:

 adjust_rel_symlink($link_path1, $link_path2);

Adjust relative symlink in $link_path2 (that used to be relative to $link_path1) so that its target now becomes relative to $link_path2.

This is useful if you copy a relative symlink e.g. $link_path1 to $link_path2. Because the target is not adjusted, and you want the new symlink to point to the original target. See example in Synopsis for illustration.

Both $link_path1 and $link_path2 must be symlink.

check_symlink

Usage:

 check_symlink(%args) -> [$status_code, $reason, $payload, \%result_meta]

Perform various checks on a symlink.

This function is not exported by default, but exportable.

Arguments ('*' denotes required arguments):

• content_matches => bool

  Whether content should match extension.

  If set to true, will guess media type from content and check that file extension exists nd matches the media type. Requires File::MimeInfo::Magic, which is only specified as a "Recommends" dependency by File-Symlink-Util distribution.

• ext_matches => bool

  Whether extension should match.

  If set to true, then if both symlink name and target filename contain filename extension (e.g. jpg) then they must match. Case variation is allowed (e.g. JPG) but other variation is not (e.g. jpeg).

• is_abs => bool

  Whether we should check that symlink target is an absolute path.

  If set to true, then symlink target must be an absolute path. If set to false, then symlink target must be a relative path.

• symlink* => filename

  Path to the symlink to be checked.

• target => filename

  Expected target path.

  If specified, then target of symlink (after normalized to absolute path) will be checked and must point to this target.

Returns an enveloped result (an array).

First element ($status_code) is an integer containing HTTP-like status code (200 means OK, 4xx caller error, 5xx function error). Second element ($reason) is a string containing error message, or something like "OK" if status is 200. Third element ($payload) is the actual result, but usually not present when enveloped result is an error response ($status_code is not 2xx). Fourth element (%result_meta) is called result metadata and is optional, a hash that contains extra information, much like how HTTP response headers provide additional metadata.

Return value: (any)

HOMEPAGE

Please visit the project's homepage at https://metacpan.org/release/File-Symlink-Util.

SOURCE

Source repository is at https://github.com/perlancar/perl-File-Symlink-Util.

SEE ALSO

Other symlink-related routines

File::Symlink::Relative provides symlink_r to create relative symlinks, which is the same as "symlink_rel".

File::MoreUtil provides file_exists and l_abs_path.

AUTHOR

perlancar <perlancar@cpan.org>

CONTRIBUTING

To contribute, you can send patches by email/via RT, or send pull requests on GitHub.

Most of the time, you don't need to build the distribution yourself. You can simply modify the code, then test via:

 % prove -l

If you want to build the distribution (e.g. to try to install it locally on your system), you can install Dist::Zilla, Dist::Zilla::PluginBundle::Author::PERLANCAR, Pod::Weaver::PluginBundle::Author::PERLANCAR, and sometimes one or two other Dist::Zilla- and/or Pod::Weaver plugins. Any additional steps required beyond that are considered a bug and can be reported to me.

COPYRIGHT AND LICENSE

This software is copyright (c) 2023, 2021 by perlancar <perlancar@cpan.org>.

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

BUGS

Please report any bugs or feature requests on the bugtracker website https://rt.cpan.org/Public/Dist/Display.html?Name=File-Symlink-Util

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.

cpanm File::Symlink::Util

perl -MCPAN -e shell
install File::Symlink::Util