Once upon a time, I put together a little function
that tries to find the canonical filename for a given
pathname on POSIX. I've finally gotten around to
turning it into a proper patch with documentation.
On non-POSIX, I made it an alias for 'abspath', as
that's the behavior on POSIX when no symlinks are
encountered in the path.
Example:
>>> os.path.realpath('/usr/bin/X11/X')
'/usr/X11R6/bin/X'
Guido van Rossum
Tim Peters
Fred Drake