xref: /freebsd/share/man/man3/pthread_mutex_consistent.3 (revision 2e3f49888ec8851bafb22011533217487764fdb0)
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28.Dd March 27, 2017
29.Dt PTHREAD_MUTEX_CONSISTENT 3
30.Os
31.Sh NAME
32.Nm pthread_mutex_consistent
33.Nd mark state protected by robust mutex as consistent
34.Sh LIBRARY
35.Lb libpthread
36.Sh SYNOPSIS
37.In pthread.h
38.Ft int
39.Fn pthread_mutex_consistent "pthread_mutex_t *mutex"
40.Sh DESCRIPTION
41If the process containing the thread owning a robust mutex terminates
42while holding the mutex, the mutex becomes inconsistent and the next thread
43that acquires the mutex lock is notified of the state by the return value
44.Er EOWNERDEAD .
45In this case, the mutex does not become normally usable again until
46the state is marked consistent.
47.Pp
48The
49.Fn pthread_mutex_consistent ,
50when called with the
51.Fa mutex
52argument, which points to the initialized robust mutex in an
53inconsistent state, marks the by mutex as consistent again.
54The consequent unlock of the mutex, by either
55.Fn pthread_mutex_unlock
56or other methods, allows other contenders to lock the mutex.
57.Pp
58If the mutex in the inconsistent state is not marked consistent
59by the call to
60.Fn pthread_mutex_consistent
61before unlock,
62further attempts to lock the
63.Fa mutex
64result in the
65.Er ENOTRECOVERABLE
66condition reported by the locking functions.
67.Sh RETURN VALUES
68If successful,
69.Fn pthread_mutex_consistent
70will return zero, otherwise an error number will be returned to
71indicate the error.
72.Sh ERRORS
73The
74.Fn pthread_mutex_lock
75function will fail if:
76.Bl -tag -width Er
77.It Bq Er EINVAL
78The mutex pointed to by the
79.Fa mutex
80argument is not robust, or is not in the inconsistent state.
81.El
82.Sh SEE ALSO
83.Xr pthread_mutex_init 3 ,
84.Xr pthread_mutex_lock 3 ,
85.Xr pthread_mutex_unlock 3 ,
86.Xr pthread_mutexattr_setrobust 3
87.Sh STANDARDS
88The
89.Fn pthread_mutex_lock
90function conforms to
91.St -susv4 .
92