1.\" Copyright (c) 1997 Brian Cully <shmit@kublai.com>
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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.\" $DragonFly: src/lib/libc_r/man/pthread_mutex_trylock.3,v 1.2 2003/06/17 04:26:48 dillon Exp $
30.\"
31.Dd July 10, 2009
32.Dt PTHREAD_MUTEX_TRYLOCK 3
33.Os
34.Sh NAME
35.Nm pthread_mutex_trylock
36.Nd attempt to lock a mutex without blocking
37.Sh LIBRARY
38.Lb libpthread
39.Sh SYNOPSIS
40.In pthread.h
41.Ft int
42.Fn pthread_mutex_trylock "pthread_mutex_t *mutex"
43.Sh DESCRIPTION
44The
45.Fn pthread_mutex_trylock
46function locks
47.Fa mutex .
48If the mutex is already locked,
49.Fn pthread_mutex_trylock
50will not block waiting for the mutex, but will return an error condition.
51.Sh RETURN VALUES
52If successful,
53.Fn pthread_mutex_trylock
54will return zero, otherwise an error number will be returned to
55indicate the error.
56.Sh ERRORS
57The
58.Fn pthread_mutex_trylock
59function will fail if:
60.Bl -tag -width Er
61.It Bq Er EINVAL
62The value specified by
63.Fa mutex
64is invalid.
65.It Bq Er EBUSY
66.Fa Mutex
67is already locked.
68.El
69.Sh SEE ALSO
70.Xr pthread_mutex_destroy 3 ,
71.Xr pthread_mutex_init 3 ,
72.Xr pthread_mutex_lock 3 ,
73.Xr pthread_mutex_unlock 3
74.Sh STANDARDS
75The
76.Fn pthread_mutex_trylock
77function conforms to
78.St -p1003.1-96 .
79