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.Dd May 5, 2020
.Dt THR_WAKE 2
.Nd wake up the suspended thread
.Fn thr_wake "long id"
This function is intended for implementing threading.
Normal applications should use
.Xr pthread_cond_timedwait 3
.Xr pthread_cond_broadcast 3
for typical safe suspension with cooperation of the thread
being suspended, or
.Xr pthread_suspend_np 3
.Xr pthread_resume_np 3
in some specific situations, instead.
Passing the thread identifier of the calling thread
.Xr thr_self 2
sets a thread's flag to cause the next signal-interruptible sleep
of that thread in the kernel to fail immediately with the
The flag is cleared by an interruptible sleep attempt or by a call to
.Xr thr_suspend 2 .
This is used by the system threading library to implement cancellation.
is not equal to the current thread identifier, the specified thread is
woken up if suspended by the
If the thread is not suspended at the time of the
call, the wake is remembered and the next attempt of the thread to
suspend itself with the
.Xr thr_suspend 2
results in immediate return with success.
Only one wake is remembered.
.Sh RETURN VALUES
.Rv -std thr_wake
operation returns these errors:
.Bl -tag -width Er
.It Bq Er ESRCH
The specified thread was not found or does not belong to the process
of the calling thread.
.Sh SEE ALSO
.Xr ps 1 ,
.Xr thr_self 2 ,
.Xr thr_suspend 2 ,
.Xr pthread_cancel 3 ,
.Xr pthread_resume_np 3 ,
.Xr pthread_suspend_np 3
system call is non-standard and is used by
.Xr pthread 3
system call first appeared in
.Fx 5.2 .