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26 .Dt PTHREAD_RWLOCK_TIMEDWRLOCK 3
29 .Nm pthread_rwlock_timedwrlock
30 .Nd "acquire a read-write lock for writing or give up after a specified period"
36 .Fn pthread_rwlock_timedwrlock "pthread_rwlock_t *restrict rwlock" "const struct timespec *restrict abs_timeout"
38 This function acquires a write lock on the read-write lock
40 However, if the lock cannot be
41 acquired without waiting for another thread to
43 this wait shall be terminated when
47 If the thread should be interrupted by a signal,
49 .Fn pthread_rwlock_timedwrlock
50 function will be automatically restarted after the thread returns from
53 The calling thread may deadlock if
54 at the time the call is made it holds
56 The results are undefined if this function is called with
57 an uninitialized read-write lock.
58 .Sh IMPLEMENTATION NOTES
59 To prevent writer starvation, writers are favored over readers.
62 .Fn pthread_rwlock_timedwrlock
63 function will return zero.
64 Otherwise, an error number will be returned to indicate the error.
66 This function shall not return an error code of
70 .Fn pthread_rwlock_timedwrlock
71 function shall fail if:
74 The lock could not be acquired before the specified timeout expired.
78 .Fn pthread_rwlock_timedwrlock
82 The calling thread already holds
85 The value specified by
87 does not refer to an initialized read-write lock object,
90 nanosecond value is less than zero or
91 greater than or equal to 1 billion.
94 .Xr pthread_rwlock_init 3 ,
95 .Xr pthread_rwlock_timedrdlock 3 ,
96 .Xr pthread_rwlock_unlock 3
99 .Fn pthread_rwlock_timedwrlock
100 function is expected to conform to
104 .Fn pthread_rwlock_timedwrlock
105 function first appeared in