AT&T and BSD Extensions to C

[Saadat Dowlati]

In every UNIX C compiler documentation that I have come across it says
that "it includes extensions existing in the AT&T and BSD compilers",
but none describes what these are. What are these?  Thanks in advance and 
please e-mail me a copy of your reply.
-- 
Saadat Dowlati		   Affiliation:	Bull HN Information Systems, Inc.
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