Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!bloom-beacon!think!ames!pacbell!pbhyf!kjk
From: kjk@pbhyf.PacBell.COM (Ken Keirnan)
Newsgroups: comp.unix.microport
Subject: Re: Compile errors on V/386 3.0E
Message-ID: <4386@pbhyf.PacBell.COM>
Date: 12 Dec 88 17:37:04 GMT
References: <680@wa3wbu.UUCP> <417@zinn.MV.COM> <273@uport.UUCP>
Reply-To: kjk@pbhyf.PacBell.COM (Ken Keirnan)
Organization: Pacific * Bell, San Ramon, CA
Lines: 52

In article <273@uport.UUCP> plocher@uport.UUCP (John Plocher) writes:

[ stuff about declaration of signal deleted ]

>
>NO!
>
>In ATT System Vr3 (Microport's V/386 2.2 & 3.0e, ISC's 1.0x, BT's 3.0...)
>signal() was changed to be of type void.  This is different from almost
>everyone else (uugh!) but that's how AT&T did it.
>
>(from <signal.h>)
>
>		extern	void(*signal())();
>		extern  void(*sigset())();
>

[ more stuff deleted ]

>
>I thought type void meant "nothing returned", yet signal is clearly type void
>and it returns something!  What don't I understand here? :-)
>
>   John Plocher


Actually, the declaration of signal() above doesn't say that signal() returns
void, but rather that signal() returns a pointer to some function that
returns "void".  Therefore, any function name given to the signal() call
should be declared void:

void doexit()
{
	(void)printf("\nGoodbye\n");
	exit(0);
}

...
...
...
	(void)signal(SIGINT, doexit);
...
...

Hope this helps.

Ken Keirnan

-- 

Ken Keirnan - Pacific Bell - {att,bellcore,sun,ames,pyramid}!pacbell!pbhyf!kjk
  San Ramon, California	                    kjk@pbhyf.PacBell.COM