xref: /freebsd/share/man/man3/pthread_mutex_lock.3 (revision 076ad2f8)
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30.Dd April 29, 2016
31.Dt PTHREAD_MUTEX_LOCK 3
32.Os
33.Sh NAME
34.Nm pthread_mutex_lock
35.Nd lock a mutex
36.Sh LIBRARY
37.Lb libpthread
38.Sh SYNOPSIS
39.In pthread.h
40.Ft int
41.Fn pthread_mutex_lock "pthread_mutex_t *mutex"
42.Sh DESCRIPTION
43The
44.Fn pthread_mutex_lock
45function locks
46.Fa mutex .
47If the mutex is already locked, the calling thread will block until the
48mutex becomes available.
49.Sh RETURN VALUES
50If successful,
51.Fn pthread_mutex_lock
52will return zero, otherwise an error number will be returned to
53indicate the error.
54.Sh ERRORS
55The
56.Fn pthread_mutex_lock
57function will fail if:
58.Bl -tag -width "Er ENOTRECOVERABLE"
59.It Bq Er EINVAL
60The value specified by
61.Fa mutex
62is invalid.
63.It Bq Er EDEADLK
64A deadlock would occur if the thread blocked waiting for
65.Fa mutex .
66.It Bq Er EOWNERDEAD
67The argument
68.Fa mutex
69points to a robust mutex and the previous owning thread terminated
70while holding the mutex lock.
71The lock was granted to the caller and it is up to the new owner
72to make the state consistent.
73.It Bq Er ENOTRECOVERABLE
74The state protected by the
75.Fa mutex
76is not recoverable.
77.El
78.Sh SEE ALSO
79.Xr pthread_mutex_consistent 3 ,
80.Xr pthread_mutex_destroy 3 ,
81.Xr pthread_mutex_init 3 ,
82.Xr pthread_mutex_trylock 3 ,
83.Xr pthread_mutex_unlock 3
84.Sh STANDARDS
85The
86.Fn pthread_mutex_lock
87function conforms to
88.St -p1003.1-96 .
89