xref: /openbsd-src/lib/libpthread/man/pthread_mutex_init.3 (revision c8b5399855d475c43e00b6f6d7f31388b0b1c442)
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3228048304Stedu.Dd $Mdocdate: January 3 2014 $
33a278733dSd.Dt PTHREAD_MUTEX_INIT 3
34c043c0f7Sd.Os
35a278733dSd.Sh NAME
36a278733dSd.Nm pthread_mutex_init
37a278733dSd.Nd create a mutex
38a278733dSd.Sh SYNOPSIS
3986f9d4cdStedu.In pthread.h
40a278733dSd.Ft int
41a278733dSd.Fn pthread_mutex_init "pthread_mutex_t *mutex" "const pthread_mutexattr_t *attr"
42a278733dSd.Sh DESCRIPTION
43a278733dSdThe
44a278733dSd.Fn pthread_mutex_init
45a278733dSdfunction creates a new mutex, with attributes specified with
46a278733dSd.Fa attr .
47a278733dSdIf
48a278733dSd.Fa attr
49096e5ce2Saaronis
50096e5ce2Saaron.Dv NULL
5128048304Steduthe default attributes are used, otherwise
5228048304Stedu.Fa attr
5328048304Stedushould be initialized by calling
5428048304Stedu.Xr pthread_mutexattr_init 3 .
5528048304Stedu.Pp
5628048304SteduA mutex may also be initialized by assignment with the macro
5728048304SteduPTHREAD_MUTEX_INITIALIZER.
58a278733dSd.Sh RETURN VALUES
59a278733dSdIf successful,
60a278733dSd.Fn pthread_mutex_init
61096e5ce2Saaronwill return zero and put the new mutex ID into
62a278733dSd.Fa mutex ,
63a278733dSdotherwise an error number will be returned to indicate the error.
64a278733dSd.Sh ERRORS
65a278733dSd.Fn pthread_mutex_init
66a278733dSdwill fail if:
67a278733dSd.Bl -tag -width Er
68a278733dSd.It Bq Er EINVAL
69a278733dSdThe value specified by
70a278733dSd.Fa attr
71a278733dSdis invalid.
72a278733dSd.It Bq Er ENOMEM
73a278733dSdThe process cannot allocate enough memory to create another mutex.
74a278733dSd.El
75a278733dSd.Sh SEE ALSO
76a278733dSd.Xr pthread_mutex_destroy 3 ,
77a278733dSd.Xr pthread_mutex_lock 3 ,
78*c8b53998Sjmc.Xr pthread_mutex_unlock 3 ,
79*c8b53998Sjmc.Xr pthread_mutexattr_init 3
80a278733dSd.Sh STANDARDS
81a278733dSd.Fn pthread_mutex_init
8282d2d131Sfgschconforms to
8382d2d131Sfgsch.St -p1003.1-96 .
84