xref: /freebsd/share/man/man3/pthread_mutex_unlock.3 (revision d37eb51047221dc3322b34db1038ff3aa533883f)
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28.Dd April 29, 2016
29.Dt PTHREAD_MUTEX_UNLOCK 3
30.Os
31.Sh NAME
32.Nm pthread_mutex_unlock
33.Nd unlock a mutex
34.Sh LIBRARY
35.Lb libpthread
36.Sh SYNOPSIS
37.In pthread.h
38.Ft int
39.Fn pthread_mutex_unlock "pthread_mutex_t *mutex"
40.Sh DESCRIPTION
41If the current thread holds the lock on
42.Fa mutex ,
43then the
44.Fn pthread_mutex_unlock
45function unlocks
46.Fa mutex .
47.Pp
48If the argument pointed by the
49.Fa mutex
50is a robust mutex in the inconsistent state, and the call to
51.Fn pthread_mutex_consistent
52function was not done prior to unlocking, further locking attempts on
53the mutex
54.Fa mutex
55are denied and locking functions return
56.Er ENOTRECOVERABLE
57error.
58.Sh RETURN VALUES
59If successful,
60.Fn pthread_mutex_unlock
61will return zero, otherwise an error number will be returned to
62indicate the error.
63.Sh ERRORS
64The
65.Fn pthread_mutex_unlock
66function will fail if:
67.Bl -tag -width Er
68.It Bq Er EINVAL
69The value specified by
70.Fa mutex
71is invalid.
72.It Bq Er EPERM
73The current thread does not hold a lock on
74.Fa mutex .
75.El
76.Sh SEE ALSO
77.Xr pthread_mutex_destroy 3 ,
78.Xr pthread_mutex_init 3 ,
79.Xr pthread_mutex_lock 3 ,
80.Xr pthread_mutex_trylock 3
81.Sh STANDARDS
82The
83.Fn pthread_mutex_unlock
84function conforms to
85.St -p1003.1-96 .
86