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29.\"
30.Dd April 29, 2016
31.Dt PTHREAD_MUTEX_UNLOCK 3
32.Os
33.Sh NAME
34.Nm pthread_mutex_unlock
35.Nd unlock a mutex
36.Sh LIBRARY
37.Lb libpthread
38.Sh SYNOPSIS
39.In pthread.h
40.Ft int
41.Fn pthread_mutex_unlock "pthread_mutex_t *mutex"
42.Sh DESCRIPTION
43If the current thread holds the lock on
44.Fa mutex ,
45then the
46.Fn pthread_mutex_unlock
47function unlocks
48.Fa mutex .
49.Pp
50If the argument pointed by the
51.Fa mutex
52is a robust mutex in the inconsistent state, and the call to
53.Fn pthread_mutex_consistent
54function was not done prior to unlocking, further locking attempts on
55the mutex
56.Fa mutex
57are denied and locking functions return
58.Er ENOTRECOVERABLE
59error.
60.Sh RETURN VALUES
61If successful,
62.Fn pthread_mutex_unlock
63will return zero, otherwise an error number will be returned to
64indicate the error.
65.Sh ERRORS
66The
67.Fn pthread_mutex_unlock
68function will fail if:
69.Bl -tag -width Er
70.It Bq Er EINVAL
71The value specified by
72.Fa mutex
73is invalid.
74.It Bq Er EPERM
75The current thread does not hold a lock on
76.Fa mutex .
77.El
78.Sh SEE ALSO
79.Xr pthread_mutex_destroy 3 ,
80.Xr pthread_mutex_init 3 ,
81.Xr pthread_mutex_lock 3 ,
82.Xr pthread_mutex_trylock 3
83.Sh STANDARDS
84The
85.Fn pthread_mutex_unlock
86function conforms to
87.St -p1003.1-96 .
88