1/***********************************************************************
2*                                                                      *
3*               This software is part of the ast package               *
4*          Copyright (c) 1985-2011 AT&T Intellectual Property          *
5*                      and is licensed under the                       *
6*                  Common Public License, Version 1.0                  *
7*                    by AT&T Intellectual Property                     *
8*                                                                      *
9*                A copy of the License is available at                 *
10*            http://www.opensource.org/licenses/cpl1.0.txt             *
11*         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12*                                                                      *
13*              Information and Software Systems Research               *
14*                            AT&T Research                             *
15*                           Florham Park NJ                            *
16*                                                                      *
17*                 Glenn Fowler <gsf@research.att.com>                  *
18*                  David Korn <dgk@research.att.com>                   *
19*                   Phong Vo <kpv@research.att.com>                    *
20*                                                                      *
21***********************************************************************/
22#pragma prototyped
23
24#include <ast.h>
25
26#if _lib_sigunblock
27
28NoN(sigunblock)
29
30#else
31
32#include <sig.h>
33
34#ifndef SIG_UNBLOCK
35#undef	_lib_sigprocmask
36#endif
37
38int
39sigunblock(int s)
40{
41#if _lib_sigprocmask
42	int		op;
43	sigset_t	mask;
44
45	sigemptyset(&mask);
46	if (s)
47	{
48		sigaddset(&mask, s);
49		op = SIG_UNBLOCK;
50	}
51	else op = SIG_SETMASK;
52	return(sigprocmask(op, &mask, NiL));
53#else
54#if _lib_sigsetmask
55	return(sigsetmask(s ? (sigsetmask(0L) & ~sigmask(s)) : 0L));
56#else
57	NoP(s);
58	return(0);
59#endif
60#endif
61}
62
63#endif
64