ls-lisp and remote files

[Lars Hansen <larsh@math.ku.dk>]

  I have been working on making ls-lisp work for remote files. To do 
that I have made a Tramp implementation of 
directory-files-and-attributes using perl on the remote machine. This 
works fine except for the translation of UID's and GID's to names. To 
make this translation, ls-lisp calls user-login-name which works in the 
context of the local machine, and that is wrong for remote directories. 
Of cource one could just let ls-lisp check if the directory is remote 
and make no translation if it is. However, I sugest the following:

1. Add an optional parameter ID-NAMES to the lisp functions 
file-attributes and directory-files-and-attributes. When ID-NAMES is 
non-nil, UID and GID is returned as names if possible.

2. Let ls-lisp use this feature to obtain UID and GID names.

I have implemented these change on my own machine (dired.c, lisp.h, 
ls-lisp.el, tramp.el) and it seems to work fine.

I want to ask people what you think about this suggestion.

----------------

One more related thing.
IFAICS it is a bug that the current implementation of ls-lisp calls 
user-login-name to obtain group name. user-login-name calls getpwuid, 
but getgrgid should be used for that, I think. It might work on 
GNU/Linux systems but it fails on Sun systems, at least the one I have 
access to. On the Sun system UID's and GID's are not disjoint.
With the changes I suggest above there is no need to make a lisp 
interface to getgrgid since the translation may be done in dired.c.