Short: Preprocessor enhancements
From: Matthew Julius <julius.2@wright.edu>
Date: Fri, 08 Jan 1999 16:29:08 -0500
Type: Feature
State: Done - implemented in 3.2.8-dev.195

Add __DIR__ and __PATH__(n) defines to the preprocessor.
  in object "/std/std/bob"
    printf("%O\n%O\n%O\n", __DIR__, __PATH__(1), __PATH__(2));
  prints
    "/std/std/"
    "/std/"
    "/"