[Linux] Man pages from pkgsrc don't get cached by native mandb

[Ottavio Caruso <ottavio2006-usenet2012%yahoo.com@localhost>]

Hi all,

I posted this question on a Linux forum but I got no replies. I'm not
sure whether the problem is with Linux or pkgsrc, but I hope you can
help.

Background: on my LMDE 3 Cindy, based on Debian Stretch, I've
installed pkgsrc as root user. This is the relevant snippet from my
mk.conf:

PKG_DBDIR=        /opt/pkg/pkgdb
LOCALBASE=        /opt/pkg
VARBASE=        /opt/pkg/var
PKG_TOOLS_BIN=        /opt/pkg/sbin
PKGINFODIR=        info
PKGMANDIR=        man

I've added /opt/pkg/bin and /opt/pkg/sbin to $PATH for both standard
and root user, plus I have added them as secure path in the global
sudo configuration file.

I didn't need to add /opt/pkg/man to $MANPATH because Debian doesn't
use $MANPATH anymore. Just running /usr/bin/manpath gives me the
correct path for both standard and root user:

$ manpath
/opt/pkg/man:/usr/local/man:/usr/local/share/man:/usr/share/man

Let's say I ask for the man page of pkgin: it works fine.

But if invoke 'whatis' or 'man -f', the man page is not found:

$ man -f pkgin
pkgin: nothing appropriate.
$ whatis  pkgin
pkgin: nothing appropriate.

I've tried to recreate a database using 'mandb' as a standard user,
but it fails. The relevant bits are (for example):

mandb: warning: cannot create catdir /opt/pkg/man/sr/cat1
warning: cannot create catdir /opt/pkg/man/sr/cat1
database /opt/pkg/man/sr/2090 is read-only
failed to open /opt/pkg/man/pl/2090 O_RDONLY
create_db(/opt/pkg/man/pl): /opt/pkg/man/pl/2090
Testing /opt/pkg/man/pl for new files
creating catdir hierarchy /opt/pkg/man/pl   Processing manual
    pages under /opt/pkg/man/pl...

Full text:
https://pastebin.com/raw/eSe96w8R

I don't have write permission on /opt, so I expect this is just  a
permission problem. I then switched to root user and I rerun the same
command. No warning issues, and it looks like mandb picks /opt/pkg/man
as a valid man directory, but no caches are generated:

# grep pkg mand.root.txt
path directory /opt/pkg/bin is not in the config file
adding /opt/pkg/man to manpath
path directory /opt/pkg/sbin is not in the config file
/opt/pkg/man is already in the manpath

Run as root, 'mandb' understands that there are man pages in
/opt/pkg/man , but doesn't cache them.

Pastebin:
https://pastebin.com/raw/8zhkauMw

Short of editing manpath configuration file (/etc/manpath.config), is
there another way for mandb to generate a cache for /opt/pkg/man?

(I'm not really sure how this would work on a native NetBSD system
because I don't have one at hand)

Thanks for reading this.

-- 
Ottavio Caruso