podlinkcheck -- check Perl pod L<> link references
podlinkcheck [--options] file-or-dir...
PodLinkCheck parses Perl POD from a script, module or documentation and checks that
L<> links within it refer to a known program, module, or man page.
L<foo> check module, pod or program "foo" L<foo/section> and check section within the pod L<bar(1)> check man page "bar(1)"
The command line is either individual files or whole directories. For a directory all the .pl, .pm and .pod files under it are checked. So for example to churn through all installed add-on modules,
Bad links are usually typos in the target page name or section name, and sometimes
L<display|target> parts the wrong way around. Occasionally there may be an
L<foo> used where just markup
I<> was intended.
External links are checked by seeking the target .pm module or .pod documentation in the
@INC path (per Pod::Find), or seeking a script (no file extension) in the usual executable
PATH. A section name in a link is checked by parsing the POD in the target file.
Module existence is also checked in the CPAN indexes with
CPANPLUS. Nothing is downloaded, just current data consulted. This covers cross-references to things not currently installed. A warning is given if a section name in a link goes unchecked because it's only on CPAN, not available locally.
Manpage links are checked by asking the
man program if it recognises the name, including any number part like
chmod(2). A manpage can also satisfy what otherwise appears to be a POD link with no sub-section, since there's often some confusion between the two.
Internal links are sometimes written
L<SYNOPSIS> # may be ambiguous
but the Perl 5.10
perlpodspec advice is to avoid ambiguity between an external module and a one-word internal section by writing a section with / or quotes,
See L</SYNOPSIS> above. # good See L<"SYNOPSIS"> above. # good
podlinkcheck warns about
L<SYNOPSIS> section links. But not if it's both an valid external module and internal section -- because it's not uncommon to have a module name as a heading or item and an
L<> link still meaning the external one.
L<> section name can use just the first word of an item or heading. This is how
Pod::Checker behaves and it's particularly good for
perlfunc cross references where just the function name can be given without the full argument list of the
The first word is everything up to the first whitespace. This doesn't come out very well on a target like
=item somefun( ARG ), but it's how
Pod::Checker 1.45 behaves. If the targets are your own then you might make the first word or full item something sensible to appear in an
If a target section is not found then
podlinkcheck will try to suggest something close, eg. differing only in punctuation or upper/lower case. Some of the POD translators may ignore upper/lower case, but it's good to write an
L<> the same as the actual target.
foo.pl:130:31: no section "constructor" in "CHI" (file /usr/share/perl5/CHI.pm) perhaps it should be "CONSTRUCTOR"
For reference, numbered
=item section names go in an
L<> without the number. This is a good thing since the numbering might change. If
podlinkcheck suggests a number in a target then it may be a mistake in the target document. A numbered item should have the number alone on the
=item and the section name as the following paragraph.
=item 1. # good The First Thing # the section name Paragraph about this thing. =item 2. The Second Thing # bad Paragraph about this next thing.
The second item "2. The Second Thing" is not a numbered item for POD purposes, but rather text that happens to start with a number. Of course sometimes that's what you want, eg.
=item 64 Bit Support
Pod::Simple for parsing and so follows its interpretation of the various hairy
L<> link forms. If an
L<> appears to be mis-interpreted you might rewrite it, perhaps with escapes like E<sol>, for the benefit of all translators which use
Pod::Simple, which in Perl 5.10 includes the basic
Pod::Checker module) checks internal links, but it doesn't check external links.
The line:column number reported for an offending
L<> is sometimes a bit off due to limited information recorded by
Pod::Simple during its parse.
CPAN::SQLite is checked first because it's fast and compact, but if a target is not found there then the
CPANPLUS caches are loaded and checked. This may use a lot of memory for a non-existent target, but it's also possible they're more up-to-date than the SQLite.
The code consulting
CPAN.pm may need a tolerably new version of that module, maybe 1.61 circa Perl 5.8.0. On earlier versions the index is not used.
The search path for installed scripts.
Used by the various
CPAN modules for the
The usual extra Perl module directories (see "ENVIRONMENT" in perlrun), which is also where link targets are sought.
Pod::Simple prior to version 3.24 didn't allow "." dots in man-page names, resulting in for example login.conf(5) being treated as a Perl module name not a man page name. If you have such links then
Pod::Simple version 3.24 or up is recommended.
Copyright 2010, 2011, 2012, 2013 Kevin Ryde
PodLinkCheck is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version.
PodLinkCheck is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with PodLinkCheck. If not, see <http://www.gnu.org/licenses/>.