xref: /freebsd/share/man/man3/pthread_cond_timedwait.3 (revision 2008043f386721d58158e37e0d7e50df8095942d)
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28.Dd May 9, 2010
29.Dt PTHREAD_COND_TIMEDWAIT 3
30.Os
31.Sh NAME
32.Nm pthread_cond_timedwait
33.Nd "wait on a condition variable for a specific amount of time"
34.Sh LIBRARY
35.Lb libpthread
36.Sh SYNOPSIS
37.In pthread.h
38.Ft int
39.Fn pthread_cond_timedwait "pthread_cond_t *cond" "pthread_mutex_t *mutex" "const struct timespec *abstime"
40.Sh DESCRIPTION
41The
42.Fn pthread_cond_timedwait
43function atomically blocks the current thread waiting on the condition
44variable specified by
45.Fa cond ,
46and releases the mutex specified by
47.Fa mutex .
48The waiting thread unblocks only after another thread calls
49.Xr pthread_cond_signal 3 ,
50or
51.Xr pthread_cond_broadcast 3
52with the same condition variable, or if the system time reaches the
53time specified in
54.Fa abstime ,
55and the current thread reacquires the lock on
56.Fa mutex .
57.Pp
58The clock used to measure
59.Fa abstime
60can be specified during creation of the condition variable using
61.Xr pthread_condattr_setclock 3 .
62.Sh RETURN VALUES
63If successful, the
64.Fn pthread_cond_timedwait
65function will return zero.
66Otherwise an error number will be returned to
67indicate the error.
68.Sh ERRORS
69The
70.Fn pthread_cond_timedwait
71function will fail if:
72.Bl -tag -width Er
73.It Bq Er EINVAL
74The value specified by
75.Fa cond ,
76.Fa mutex
77or
78.Fa abstime
79is invalid.
80.It Bq Er ETIMEDOUT
81The system time has reached or exceeded the time specified in
82.Fa abstime .
83.It Bq Er EPERM
84The specified
85.Fa mutex
86was not locked by the calling thread.
87.El
88.Sh SEE ALSO
89.Xr pthread_cond_broadcast 3 ,
90.Xr pthread_cond_destroy 3 ,
91.Xr pthread_cond_init 3 ,
92.Xr pthread_cond_signal 3 ,
93.Xr pthread_cond_wait 3 ,
94.Xr pthread_condattr_setclock 3
95.Sh STANDARDS
96The
97.Fn pthread_cond_timedwait
98function conforms to
99.St -p1003.1-96 .
100