How to list the available languages for a man page?

Question

I have just found out that it is possible to display man pages in different laguages using the -L option (e.g. man -L fr man shows a man page in French). However, when a language is not available, an American English man page is usually shown. I do not prefer to read man pages in American English if one of my other languages is available.

How can I know what languages are available in advance?

It would be great if there is a command (e.g. man --list-languages cal) that outputs something like:

ar
de
en
my
zh

Answer 1

How about:

#!/usr/bin/env bash

if [ "$#" -eq 2 ]
then
    printf -v man_arg "%s %s" "$1" "$2"
elif [ "$#" -eq 1 ]
then
    printf -v man_arg "%s" "$1"
else
    printf "Wrong number of args\n" >&2
    exit 1
fi

LANG=C

mandir="$(dirname "$(dirname "$(man -w $man_arg)")")"
manfile="$(basename "$(man -w $man_arg)")"
part_to_rm="$(basename "$(dirname "$(man -w $man_arg)")")"

find "$mandir" -name "$manfile" | cut -d / -f4 | sed "/$part_to_rm/ d"

This script will display all languages that given manpage is available in besides English. Examples:

$ ./man-langs.sh cal
ja
$ ./man-langs.sh man
nl
pl
es
da
it
ja
de
zh_CN
ru
id
fr
$ ./man-langs.sh  xfce4-terminal
pl
es
sr
sv
da
pt
lt
it
ja
ar
gl
pt_BR
ca
el
de
ko
zh_CN
tr
ru
id
uk
ug
fr
$ ./man-langs.sh 1 printf
ja