xref: /freebsd/share/man/man3/pthread_mutex_trylock.3 (revision 380a989b3223d455375b4fae70fd0b9bdd43bafb)
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28.Dd July 30, 1998
29.Dt PTHREAD_MUTEX_TRYLOCK 3
30.Os BSD 4
31.Sh NAME
32.Nm pthread_mutex_trylock
33.Nd attempt to lock a mutex without blocking
34.Sh SYNOPSIS
35.Fd #include <pthread.h>
36.Ft int
37.Fn pthread_mutex_trylock "pthread_mutex_t *mutex"
38.Sh DESCRIPTION
39The
40.Fn pthread_mutex_trylock
41function locks
42.Fa mutex .
43If the mutex is already locked,
44.Fn pthread_mutex_trylock
45will not block waiting for the mutex, but will return an error condition.
46.Sh RETURN VALUES
47If successful,
48.Fn pthread_mutex_trylock
49will return zero, otherwise an error number will be returned to
50indicate the error.
51.Sh ERRORS
52.Fn pthread_mutex_trylock
53will fail if:
54.Bl -tag -width Er
55.It Bq Er EINVAL
56The value specified by
57.Fa mutex
58is invalid.
59.It Bq Er EBUSY
60.Fa Mutex
61is already locked.
62.El
63.Pp
64.Sh SEE ALSO
65.Xr pthread_mutex_destroy 3 ,
66.Xr pthread_mutex_init 3 ,
67.Xr pthread_mutex_lock 3 ,
68.Xr pthread_mutex_unlock 3
69.Sh STANDARDS
70.Fn pthread_mutex_trylock
71conforms to ISO/IEC 9945-1 ANSI/IEEE
72.Pq Dq Tn POSIX
73Std 1003.1 Second Edition 1996-07-12.
74