patch to realpath(3) to make it DTRT(IMO) with variant symlinks

[Matthew Dillon]

:...
:> quite probably not the best way, but it seems to work (it's been
:> modestly tested.)  Other ways to address it might be:
:> 
:> - just don't make realpath resolve variant symlinks
:> 
:> I think that leaves the spirit (if not the letter) of realpath broken.
:> Existing scripts expect realpath(1) to return a real genuine filename.

    realpath() is used to resolve paths, so I would say that it *should*
    resolve varsyms.
 
:> - make readlink(2) resolve variant symlinks instead
:
:IMO this is the correct way.

    No, we can't do this.  Many programs use symlinks to store binary or
    near-binary data.  It has to be WYSIWYG.  And, besides, when you ls -lda
    a symlink you want to see the ${}'s, not the post-resolved data.

:> - make varsymreplace a syscall
:> 
:> Too rich for my blood :)  Could be better for consistency though (e.g.
:> my patch doesn't check vfs.varsym_enable; it probably should.)
:
:I don't like that one too. If Matt doesn't cry out loud, I'll change
:the kernel source to allow them to share the implementation.
:
:Joerg
:> -Chris
:

    Huh?  No new syscall is needed as far as I can tell.  realpath() is the
    only procedure which might conceivably need to resolve a varsym.

					-Matt
					Matthew Dillon 
					<dillon at xxxxxxxxxxxxx>