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[worley at world.std.com (Dale R Worley)]

   From: mikebw at bilow.bilow.uu.ids.net (Mike Bilow)

   Logically, the program which calls 'gs' must be running from some
   directory.  Assuming that these two programs are running out of
   different directories, you need to define links named 'gs' in these
   two directories, each to the proper 'gs' executable.  Then, if your
   global search path has '.' early on, then the appropriate link
   ('./gs') will always be found for each parent program.  If a parent
   program and its 'gs' are actually in the same directory, then you
   don't even need the link.

Unfortunately, it isn't so.  People have wanted this idea to work for
years in Unix, but it can't really be done.

The dot refers to the current directory of the process, not the
directory from which the current executable image was loaded.  In
particular, if I am in my home directory (/users/worley) and run, say,
mv (/bin/mv), then in the process running mv, the "." in the PATH
refers to /users/worley, not /bin/mv.

One would think that one could invent a new special directory name to
mean "the directory in which the current executable resides" (Multics
has this concept), but it can't be done, because that directory has
no unambiguous definition -- the executable file can be hardlinked
from several different directories, and all of the links to the file
are equal.

Dale
--
Dale R. Worley					Ariadne Internet Services
Voice: +1 617-899-7949   Fax: +1 617-899-7946	E-mail: worley at ariadne.com
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