]> git.saurik.com Git - apple/libc.git/blame - sys/sigwait.2
Libc-391.5.18.tar.gz
[apple/libc.git] / sys / sigwait.2
CommitLineData
5b2abdfb
A
1.\" Copyright (C) 2000 Jason Evans <jasone@FreeBSD.org>.
2.\" All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\" notice(s), this list of conditions and the following disclaimer as
9.\" the first lines of this file unmodified other than the possible
10.\" addition of one or more copyright notices.
11.\" 2. Redistributions in binary form must reproduce the above copyright
12.\" notice(s), this list of conditions and the following disclaimer in
13.\" the documentation and/or other materials provided with the
14.\" distribution.
15.\"
16.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
17.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
20.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
23.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
25.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
26.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27.\"
28.\" $FreeBSD: src/lib/libc_r/man/sigwait.3,v 1.7 2001/10/01 16:09:09 ru Exp $
29.Dd April 27, 2000
30.Dt SIGWAIT 2
31.Os
32.Sh NAME
33.Nm sigwait
34.Nd select a set of signals
35.Sh SYNOPSIS
36.In signal.h
37.Ft int
38.Fn sigwait "const sigset_t *set" "int *sig"
39.Sh DESCRIPTION
40The
41.Fn sigwait
42function selects a set of signals, specified by
43.Fa set .
44If none of the selected signals are pending,
45.Fn sigwait
46waits until one or more of the selected signals has been generated.
47Then
48.Fn sigwait
49atomically clears one of the selected signals from the set of pending signals
50for the process and sets the location pointed to by
51.Fa sig
52to the signal number that was cleared.
53.Pp
54The signals specified by
55.Fa set
9385eb3d 56should be blocked, but not ignored, at the time of the call to
5b2abdfb 57.Fn sigwait .
9385eb3d
A
58.Pp
59Processes which call
60.Fn sigwait
61on ignored signals will wait indefinately. Ignored
62signals are dropped immeadiately by the system, before delivery
63to a waiting process.
5b2abdfb
A
64.Sh RETURN VALUES
65If successful,
66.Fn sigwait
67returns 0 and sets the location pointed to by
68.Fa sig
69to the cleared signal number.
70Otherwise, an error number is returned.
71.Sh ERRORS
72.Fn sigwait
73will fail if:
74.Bl -tag -width Er
75.It Bq Er EINVAL
76.Fa set
77specifies one or more invalid signal numbers.
78.El
79.Sh SEE ALSO
80.Xr sigaction 2 ,
81.Xr sigpending 2 ,
82.Xr sigsuspend 2 ,
83.Xr pause 3 ,
84.Xr pthread_sigmask 2
85.Sh STANDARDS
86.Fn sigwait
87conforms to ISO/IEC 9945-1:1996 (``POSIX.1'')