RE: testing for a remote file to include file on a Windows mappeddrive

[Drew Adams]

> > Googling showed that local drive vs mapped network drive can be
> > tested, in C# at least (using GetDriveType() or
> > DriveInfo.DriveType). I didn't come
> > across a way to test it from C, however.
>
> GetDriveType can be called from C. Emacs already uses it in w32.c, but
> only to determine which drives are fixed, thus their information can be
> cached indefinitely.

Good. Do you agree that it would be good for either `file-remote-p' or some
new function to take mapped network drives into account for remote files?

It might be that some uses of `file-remote-p' should not consider a file on
a network drive to be remote - I don't know.

Also, IIUC, `file-remote-p' isn't only boolean; the non-nil return value
means something. I don't know what should be returned for a file on a mapped
network drive.

And should we perhaps have a function that distinguishes remote files that
are not on a mapped drive from those that are? Is there any need to
distinguish these? (We currently do distinguish them, in that
`file-remote-p' returns non-nil for the former and nil for the latter.)