Re: file-relative-name and remote files

[Richard Stallman]

    There are two functions we're talking about, expand-file-name and
    file-relative-name.

The questions are linked.  If expand-file-name lets .. get rid
of a remote prefix, then file-relative-name can use .. to do that.
If expand-file-name does not let .. cancel a remote prefix,
then file-relative-name should treat the local and remote names
as being in "separate trees"; it should return an absolute file name
when the DIRECTORY arg includes a remote prefix and FILENAME does not.
For symmetry, it should also return an absolute file name when
the FILENAME arg includes a remote prefix and DIRECTORY does not.

I am leading towards thinking that we should choose the second
alternative.  That means installing Lars' change in file-relative-name,
and changing Tramp so that (expand-file-name "/foo:/../bar")
returns "/foo:/../bar".

The change we're considering in expand-file-name seems to be needed also.