xref: /freebsd/lib/libc/gen/pause.3 (revision 8aac90f18aef7c9eea906c3ff9a001ca7b94f375)
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28.Dd April 3, 2022
29.Dt PAUSE 3
30.Os
31.Sh NAME
32.Nm pause
33.Nd stop until signal
34.Sh LIBRARY
35.Lb libc
36.Sh SYNOPSIS
37.In unistd.h
38.Ft int
39.Fn pause void
40.Sh DESCRIPTION
41.Sy Pause is made obsolete by
42.Xr sigsuspend 2 .
43.Pp
44The
45.Fn pause
46function
47forces a process to pause until
48a signal is received from either the
49.Xr kill 2
50function
51or an interval timer.
52(See
53.Xr setitimer 2 . )
54Upon termination of a signal handler started during a
55.Fn pause ,
56the
57.Fn pause
58call will return.
59.Sh RETURN VALUES
60Always returns \-1.
61.Sh ERRORS
62The
63.Fn pause
64function
65always returns:
66.Bl -tag -width Er
67.It Bq Er EINTR
68The call was interrupted.
69.El
70.Sh SEE ALSO
71.Xr kill 2 ,
72.Xr select 2 ,
73.Xr sigsuspend 2
74.Sh HISTORY
75A
76.Fn pause
77system call first appeared in the Programmer's Workbench (PWB/UNIX)
78and was then ported to
79.At v7 .
80It was reimplemeted as a wrapper around the
81.Fn sigpause
82and
83.Fn sigblock
84system calls in
85.Bx 4.2 ,
86and around the
87.Xr sigsuspend 2
88and
89.Xr sigprocmask 2
90system calls in
91.Bx 4.3 Reno .
92