1.\" $OpenBSD: pthread_mutex_init.3,v 1.8 2003/05/18 13:06:33 jmc Exp $
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3.\" Copyright (c) 1997 Brian Cully <shmit@kublai.com>
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30.\" $FreeBSD: pthread_mutex_init.3,v 1.6 1999/08/28 00:03:07 peter Exp $
31.\"
32.Dd July 29, 1998
33.Dt PTHREAD_MUTEX_INIT 3
34.Os
35.Sh NAME
36.Nm pthread_mutex_init
37.Nd create a mutex
38.Sh SYNOPSIS
39.Fd #include <pthread.h>
40.Ft int
41.Fn pthread_mutex_init "pthread_mutex_t *mutex" "const pthread_mutexattr_t *attr"
42.Sh DESCRIPTION
43The
44.Fn pthread_mutex_init
45function creates a new mutex, with attributes specified with
46.Fa attr .
47If
48.Fa attr
49is
50.Dv NULL
51the default attributes are used.
52.Sh RETURN VALUES
53If successful,
54.Fn pthread_mutex_init
55will return zero and put the new mutex ID into
56.Fa mutex ,
57otherwise an error number will be returned to indicate the error.
58.Sh ERRORS
59.Fn pthread_mutex_init
60will fail if:
61.Bl -tag -width Er
62.It Bq Er EINVAL
63The value specified by
64.Fa attr
65is invalid.
66.It Bq Er ENOMEM
67The process cannot allocate enough memory to create another mutex.
68.It Bq Er EAGAIN
69The system temporarily lacks the resources to create another mutex.
70.El
71.Sh SEE ALSO
72.Xr pthread_mutex_destroy 3 ,
73.Xr pthread_mutex_lock 3 ,
74.Xr pthread_mutex_trylock 3 ,
75.Xr pthread_mutex_unlock 3
76.Sh STANDARDS
77.Fn pthread_mutex_init
78conforms to
79.St -p1003.1-96 .
80