-/* On Ultrix 4.3, getgroups (0, 0) always fails.
- This function handles that special case and lets the system-
- provided function handle all others. */
+/* On at least Ultrix 4.3 and NextStep 3.2, getgroups (0, 0) always fails.
+ On other systems, it returns the number of supplemental groups for the
+ process. This function handles that special case and lets the system-
+ provided function handle all others. */