NetBSD-5.0.2/lib/libpthread/pthread_spin_destroy.3

.\" $NetBSD: pthread_spin_destroy.3,v 1.6 2008/05/26 08:45:55 wiz Exp $
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.Dd May 26, 2008
.Dt PTHREAD_SPIN_DESTROY 3
.Os
.Sh NAME
.Nm pthread_spin_destroy
.Nd destroy a spin lock
.Sh LIBRARY
.Lb libpthread
.Sh SYNOPSIS
.In pthread.h
.Ft int
.Fn pthread_spin_destroy "pthread_spinlock_t *lock"
.Sh DESCRIPTION
The
.Fn pthread_spin_destroy
function is used to destroy a spin lock previously created with
.Fn pthread_spin_init .
.Sh RETURN VALUES
If successful, the
.Fn pthread_spin_destroy
function will return zero.
Otherwise an error number will be returned to indicate the error.
.Sh ERRORS
The
.Fn pthread_spin_destroy
function may fail if:
.Bl -tag -width Er
.It Bq Er EBUSY
The system has detected an attempt to destroy the object referenced by
.Fa lock
while it is locked.
.It Bq Er EINVAL
The value specified by
.Fa lock
is invalid.
.El
.Sh SEE ALSO
.Xr pthread_spin_init 3 ,
.Xr pthread_spin_lock 3 ,
.Xr pthread_spin_trylock 3 ,
.Xr pthread_spin_unlock 3
.Sh STANDARDS
.Fn pthread_spin_destroy
conforms to
.St -p1003.1-2001 .
.Sh CAVEATS
Applications using spinlocks are vulnerable to the effects of priority
inversion.
Applications using real-time threads
.Pq Dv SCHED_FIFO , SCHED_RR
should not use these interfaces.
Outside carefully controlled environments, priority inversion with spinlocks
can lead to system deadlock.
Mutexes are preferable in nearly every possible use case.