xref: /openbsd-src/lib/libpthread/man/pthread_cond_wait.3 (revision 86f9d4cdda0e0267dccd8755ac0035525579c4a7)
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282d2d131Sfgsch.\"
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3074493c91Sd.\" $FreeBSD: pthread_cond_wait.3,v 1.6 1999/08/28 00:03:04 peter Exp $
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32*86f9d4cdStedu.Dd $Mdocdate: June 5 2013 $
33a278733dSd.Dt PTHREAD_COND_WAIT 3
34c043c0f7Sd.Os
35a278733dSd.Sh NAME
36a278733dSd.Nm pthread_cond_wait
37a278733dSd.Nd wait on a condition variable
38a278733dSd.Sh SYNOPSIS
39*86f9d4cdStedu.In pthread.h
40a278733dSd.Ft int
41a278733dSd.Fn pthread_cond_wait "pthread_cond_t *cond" "pthread_mutex_t *mutex"
42a278733dSd.Sh DESCRIPTION
43a278733dSdThe
44a278733dSd.Fn pthread_cond_wait
45a278733dSdfunction atomically blocks the current thread waiting on the condition
46a278733dSdvariable specified by
47a278733dSd.Fa cond ,
48a278733dSdand unblocks the mutex specified by
49a278733dSd.Fa mutex .
50a278733dSdThe waiting thread unblocks only after another thread calls
51ee997aeaSmpech.Xr pthread_cond_signal 3 ,
52ee997aeaSmpechor
53a278733dSd.Xr pthread_cond_broadcast 3
54379cec13Spvalchevwith the same condition variable, and the current thread reacquires the lock
55a278733dSdon
56a278733dSd.Fa mutex .
57a278733dSd.Sh RETURN VALUES
58a278733dSdIf successful, the
59a278733dSd.Fn pthread_cond_wait
60ee997aeaSmpechfunction will return zero.
61ee997aeaSmpechOtherwise an error number will be returned to indicate the error.
62a278733dSd.Sh ERRORS
63a278733dSd.Fn pthread_cond_wait
64a278733dSdwill fail if:
65a278733dSd.Bl -tag -width Er
66a278733dSd.It Bq Er EINVAL
67a278733dSdThe value specified by
68a278733dSd.Fa cond
69a278733dSdor the value specified by
7074493c91Sd.Fa mutex
71a278733dSdis invalid.
72a278733dSd.El
73a278733dSd.Sh SEE ALSO
74f8344ebdSd.Xr pthread_cond_broadcast 3 ,
75a278733dSd.Xr pthread_cond_destroy 3 ,
76f8344ebdSd.Xr pthread_cond_init 3 ,
77a278733dSd.Xr pthread_cond_signal 3 ,
78f8344ebdSd.Xr pthread_cond_timedwait 3
79a278733dSd.Sh STANDARDS
80a278733dSd.Fn pthread_cond_wait
8182d2d131Sfgschconforms to
8282d2d131Sfgsch.St -p1003.1-96 .
83