xref: /original-bsd/lib/libc/gen/signal.c (revision b4971bb3)
1 /*
2  * Copyright (c) 1985, 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #if defined(LIBC_SCCS) && !defined(lint)
9 static char sccsid[] = "@(#)signal.c	8.1 (Berkeley) 06/04/93";
10 #endif /* LIBC_SCCS and not lint */
11 
12 /*
13  * Almost backwards compatible signal.
14  */
15 #include <signal.h>
16 
17 sigset_t _sigintr;		/* shared with siginterrupt */
18 
19 sig_t
20 signal(s, a)
21 	int s;
22 	sig_t a;
23 {
24 	struct sigaction sa, osa;
25 
26 	sa.sa_handler = a;
27 	sigemptyset(&sa.sa_mask);
28 	sa.sa_flags = 0;
29 	if (!sigismember(&_sigintr, s))
30 		sa.sa_flags |= SA_RESTART;
31 	if (sigaction(s, &sa, &osa) < 0)
32 		return (SIG_ERR);
33 	return (osa.sa_handler);
34 }
35