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From: jim@jagmac2.gsfc.nasa.gov (Jim Jagielski)
Newsgroups: comp.unix.aux
Subject: signal.h and sys/signal.h on 2.0
Message-ID: <3392@dftsrv.gsfc.nasa.gov>
Date: 12 Sep 90 18:10:07 GMT
Sender: news@dftsrv.gsfc.nasa.gov
Reply-To: jim@jagmac2.gsfc.nasa.gov (Jim Jagielski)
Organization: NASA Goddard Space Flight Center
Lines: 41

I have uncovered something in the A/UX 2.0 header files for signals
(/usr/include/signal.h and sys/signal.h) that, if I understand typedefs
right, might be wrong.

In signal.h, signal is defined as:

	extern sigfunct_t signal();

In sys/signal.h, sigfunct_t is defined as (assume !POSIX case):

	typedef int (*sigfunct_t) ();

which means that sigfunct_t is a type that is a "pointer to a function
that returns an int."

Now this definition of sigfunct_t is fine. My concern is back in signal.h.
What we want to say is:

	int (*signal)();

which would be accomplished by:

	sigfunct_t signal;
	("signal is a pointer to a function that returns an int")

but signal.h says something different (I think...):

	sigfunct_t signal();
	("signal is a function that returns a pointer to a function that
	  returns an int")

IS THIS RIGHT??? DO I UNDERSTAND THIS CORRECTLY???
--
=======================================================================
#include <std/disclaimer.h>
                                 =:^)
           Jim Jagielski                    NASA/GSFC, Code 711.1
     jim@jagmac2.gsfc.nasa.gov               Greenbelt, MD 20771

"Kilimanjaro is a pretty tricky climb. Most of it's up, until you reach
 the very, very top, and then it tends to slope away rather sharply."