What does SUID, SGID and Sticky bits do on inappropriate files?

[Tom Reingold]

Here is some more (paraphrased) information from my System V Release 3
manual page for ls(1):

if doing "ls -l" on a file yields

-rwSrwlr-T  1 tr       other          10 Dec 27 16:35 file

then 

   1. The 'S' means the set-uid bit is on but the user-execute bit is
   off.  This is undefined.

   2. The 'l' means the set-gid bit is on but the group-execute bit is
   off.  This means mandatory locking will occur during access.

   3. The 'T' means the sticky bit is on but execution is off.  This is
   undefined.
--
        Tom Reingold
        tr at samadams.princeton.edu  OR  ...!princeton!samadams!tr
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