Feature: support dman

[JingMatrix]

Is it possible to automatically use dman command on linux to search for man page online?

We need it, for example, when there is no manpage avaible locally.

[lucc]

@JingMatrix hello I don't fully understand your question just yet. Maybe you can explain a bit more.

What is dman? I can not find any info about it. Do you have a link?

If you execute man something then the man program will look for a manual page for "something". If it does find one it will call your pager (so nvimpager :) but if man does not find a man page, it does not call nvimpager. So there might be little we can do about your problem. But maybe I do not understand your problem correctly?

[JingMatrix]

Sorry for that my issue is too short.

Infomation of dman is here:

http://manpages.ubuntu.com/manpages/impish/man1/dman.1.html

I understand that nvimpager is just a pager. My situation is that, when I use nvimpager for some manual page and try to jump to a possible keyword (pressing k, equivalent to ctrl + click), nvim give an error such as "no manual found for xxx" if there is no manual for that command installed.

What I hope is that nvimpager could handld this error by using dman to search on line manual and print it.

[lucc]

It looks like dman is specific for ubuntu and only exists there (tell me if I'm wrong!). I am not using ubuntu so it might be difficult for me to develop something that only exists on ubuntu. And I am not sure if I want to add and maintain a feature in nvimpager that is specific to ubuntu only.

But I have two ideas for you:

1. hack the K keybinding in nvimpager

When you press K in nvimpager you are most probably calling the man plugin that is shipped with nvim. Check

:verbose map K
n  K           *@:Man<CR>
        Last set from /nix/store/70ndw4jcrjkbqk89dlyhr730i4pl9fmk-neovim-unwrapped-0.4.4/share/nvim/runtime/ftplugin/man.vim line 28
:verbose command Man
    Name        Args       Address   Complete  Definition
!   Man         *    0               customlist    if <bang>0 | set ft=man | else | call man#open_page(v:count, v:count1, <q-mods>, <f-args>) | endif
        Last set from /nix/store/70ndw4jcrjkbqk89dlyhr730i4pl9fmk-neovim-unwrapped-0.4.4/share/nvim/runtime/plugin/man.vim line 10

(the long path in the beginning is from my OS (NixOS) but the important part is that K is mapped by a default neovim plugin.

So the first thing you can try is to check for the error that :Man gives you and then call dman somehow.

2. wrap man on your system globally

You could write a short shell script that calls /usr/bin/man (or whatever the correct path is) and if that fails tries to call dman instead. Call it man and place it in your $PATH before the original man. That should "fix" K in nvimpager but also in plain nvim and also man on the command line.

[JingMatrix]

Thank you, now I understand it is more related to the man.vim provided by nvim.

I tried your second solution, not working. Nvim seems hard-code something related to exit on any command fail. My following code could not use dman automatically in nvim.

#! /bin/zsh

[[ $1 == "-w" ]] && shift
if [[ $# -eq 1 ]]; then
    if /bin/man -w $1 2&>1 >/dev/null; then
        /bin/man $1
    else
        /bin/dman $1
    fi
else
    /bin/man $@
fi

[lucc]

You have to accept more options because the man.vim file passes many options to man. Check the autoload/man.vim file, the s:get_page function and the s:localfile_arg variable.

[lucc]

PS: does it at least work from the command line?

[JingMatrix]

Yes, it works in terminal.

From man.vim, I got to know their logic is read local file. This is not compatiable with dman, which I believe is put manual into stdout.

Thanks for you kind help