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28.\" $FreeBSD: src/share/man/man3/pthread_mutex_trylock.3,v 1.15 2007/10/22 10:08:00 ru Exp $
29.\"
30.Dd July 10, 2009
31.Dt PTHREAD_MUTEX_TRYLOCK 3
32.Os
33.Sh NAME
34.Nm pthread_mutex_trylock
35.Nd attempt to lock a mutex without blocking
36.Sh LIBRARY
37.Lb libpthread
38.Sh SYNOPSIS
39.In pthread.h
40.Ft int
41.Fn pthread_mutex_trylock "pthread_mutex_t *mutex"
42.Sh DESCRIPTION
43The
44.Fn pthread_mutex_trylock
45function locks
46.Fa mutex .
47If the mutex is already locked,
48.Fn pthread_mutex_trylock
49will not block waiting for the mutex, but will return an error condition.
50.Sh RETURN VALUES
51If successful,
52.Fn pthread_mutex_trylock
53will return zero, otherwise an error number will be returned to
54indicate the error.
55.Sh ERRORS
56The
57.Fn pthread_mutex_trylock
58function will fail if:
59.Bl -tag -width Er
60.It Bq Er EINVAL
61The value specified by
62.Fa mutex
63is invalid.
64.It Bq Er EBUSY
65.Fa Mutex
66is already locked.
67.El
68.Sh SEE ALSO
69.Xr pthread_mutex_destroy 3 ,
70.Xr pthread_mutex_getprioceiling 3 ,
71.Xr pthread_mutex_init 3 ,
72.Xr pthread_mutex_lock 3 ,
73.Xr pthread_mutex_setprioceiling 3 ,
74.Xr pthread_mutex_timedlock 3 ,
75.Xr pthread_mutex_unlock 3
76.Sh STANDARDS
77The
78.Fn pthread_mutex_trylock
79function conforms to
80.St -p1003.1-96 .
81