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31.Dd March 27, 2017
32.Dt PTHREAD_MUTEX_CONSISTENT 3
33.Os
34.Sh NAME
35.Nm pthread_mutex_consistent
36.Nd mark state protected by robust mutex as consistent
37.Sh LIBRARY
38.Lb libpthread
39.Sh SYNOPSIS
40.In pthread.h
41.Ft int
42.Fn pthread_mutex_consistent "pthread_mutex_t *mutex"
43.Sh DESCRIPTION
44If the thread owning a robust mutex terminates while holding the
45mutex, the mutex becomes inconsistent and the next thread that
46acquires the mutex lock is notified of the state by the return value
47.Er EOWNERDEAD .
48In this case, the mutex does not become normally usable again until
49the state is marked consistent.
50.Pp
51The
52.Fn pthread_mutex_consistent ,
53when called with the
54.Fa mutex
55argument, which points to the initialized robust mutex in an
56inconsistent state, marks the by mutex as consistent again.
57The consequent unlock of the mutex, by either
58.Fn pthread_mutex_unlock
59or other methods, allows other contenders to lock the mutex.
60.Pp
61If the mutex in the inconsistent state is not marked consistent
62by the call to
63.Fn pthread_mutex_consistent
64before unlock,
65further attempts to lock the
66.Fa mutex
67result in the
68.Er ENOTRECOVERABLE
69condition reported by the locking functions.
70.Sh RETURN VALUES
71If successful,
72.Fn pthread_mutex_consistent
73will return zero, otherwise an error number will be returned to
74indicate the error.
75.Sh ERRORS
76The
77.Fn pthread_mutex_lock
78function will fail if:
79.Bl -tag -width Er
80.It Bq Er EINVAL
81The mutex pointed to by the
82.Fa mutex
83argument is not robust, or is not in the inconsistent state.
84.El
85.Sh SEE ALSO
86.Xr pthread_mutex_init 3 ,
87.Xr pthread_mutex_lock 3 ,
88.Xr pthread_mutex_unlock 3 ,
89.Xr pthread_mutexattr_setrobust 3
90.Sh STANDARDS
91The
92.Fn pthread_mutex_lock
93function conforms to
94.St -susv4 .
95