Re: [PATCH] user/group completion for dired

[Dmitry Antipov <dmantipov@yandex.ru>]

On 09/21/2011 12:49 PM, Eli Zaretskii wrote:

> IMO, the last two sentences are too categorical and too OS-specific.
> E.g., in the MS-DOS build of Emacs, getpwent and getgrent are
> available and usable, although MS-DOS is certainly not a Unix system.
> It should also be possible to write an emulation of these functions
> for MS-Windows.  And even on Unix systems, I'm not sure the
> information is always on /etc/passwd.  And the same goes for groups
> and /etc/groups.
>
> So please make the doc strings more vague; it should be enough to say
> that if this functionality is not supported, the value is nil, or
> something like that.

OK. I realize that receiving the list of system users/groups may require
NSS/LDAP/whatever queries. On GNU/Linux system, it should be possible
to interface libuser; other systems might have the similar methods,
but I'm not sure it's worth playing with them just for input completion
task.

> We should at least return the single user that is the current user,
> instead of nil.  Emacs always knows who is the current user, on all
> supported systems, so there's no need to be so restrictive when
> getpwent is unavailable.

OK, I guess it should be Vuser_real_login_name.

> What happens if the user name includes non-ASCII characters?  If that
> can happen, we should decode the pw_name string, not just call
> build_string on the unibyte string we get.  Same issue with the group
> name.

Comment around build_string() says it should guess about string data
and produce multibyte string if necessary. On my system (Fedora 15)
it was able to decode and represent tõendidütles (no ideas what language
it is and what does it mean :-) as multibyte string.

Dmitry