man: not all man pages are listed if MANPATH environment is set

[yuwata]

If MANPATH environment is set, only man pages located under directories specified by MANPATH are shown.

e.g.,

$ echo $MANPATH
/usr/share/man/openmpi-x86_64:/usr/share/lmod/lmod/share/man::
$ man ma(tab)
(no output)
$ man MPI(tab)
MPI
MPI_Abort
(snip)

$ unset MANPATH
$ man ma(tab)
mac2unix
machinectl
(snip)
$ man MPI(tab)
(no output)

As explained in manpath.1

If $MANPATH is set, manpath displays its value rather than determining it on the fly. If $MANPATH is prefixed by a colon, then the value of the variable is appended to the list determined from the content of the configuration files. If the colon comes at the end of the value in the variable, then the determined list is appended to the content of the variable. If the value of the variable contains a double colon (::), then the determined list is inserted in the middle of the value, between the two colons.

I think in the completion for man should use the output of manpath command.

I found this issue on Fedora 24 with Lmod package.

[ackalker]

Sadly, the suggested fix doesn't work with the mdocml package installed by default in Void Linux, which has neither a manpath command nor a -w option to man (which in this case is a symlink to mandoc). In this case I see no other solution but to process both /etc/man.conf and the MANPATH variable when completing.

[ackalker]

Actually, there is another way to get completion candidates (including manual pages in directories in user-supplied MANPATH) using mdocml's apropos command with a regex.
To get all completion candidates for the prefix perlc:

$ echo $MANPATH
:/home/miki/perl5/man/
$ apropos 'Nm~^perlc'|sed -e 's/(.*$//'
perlcall
perlce
perlcheat
perlclib
perlcn
perlcommunity
perlcritic
perlcygwin

Note that this includes the candidate perlcritic, which comes from the corresponding Perl module which I installed locally in /home/miki/perl5. For this to work I needed to run makewhatis as regular user, to create the database /home/miki/perl5/man/mandoc.db, which is used by apropos.

[tornaria]

A fix is in 2af2986 (see PR #116), using man -k.

Tested to work with both with man-db and with mdocml. Indeed the PR creates a number of new test cases which include a test for this bug.

[inconstante]

I think that commit ID e6a4715 fixes this problem. Can this bug be closed?

[tornaria]

It doesn't, as explained above. In my system (void linux, which uses mdocml as man)

$ manpath
bash: manpath: command not found
$ man -w
usage: man [-acfhklw] [-C file] [-M path] [-m path] [-S subsection]
	   [[-s] section] name ...

So essentially the manpath becomes hardcoded.

There is a more robust fix including tests for this and other cases in PR #116.