NAME
pthread_spin_lock,
pthread_spin_trylock,
pthread_spin_unlock —
lock or unlock a spin lock
LIBRARY
library “libpthread”
SYNOPSIS
#include
<pthread.h>
int
pthread_spin_lock(pthread_spinlock_t
*lock);
int
pthread_spin_trylock(pthread_spinlock_t
*lock);
int
pthread_spin_unlock(pthread_spinlock_t
*lock);
DESCRIPTION
Thepthread_spin_lock()
function will acquire lock if it is not currently owned
by another thread. If the lock cannot be acquired immediately, it will spin
attempting to acquire the lock (it will not sleep) until it becomes available.
The
pthread_spin_trylock()
function is the same as pthread_spin_lock() except
that if it cannot acquire lock immediately it will
return with an error.
The
pthread_spin_unlock()
function will release lock, which must have been
previously locked by a call to pthread_spin_lock()
or pthread_spin_trylock().
RETURN VALUES
If successful, all these functions will return zero. Otherwise, an error number will be returned to indicate the error.
None of these functions will return
EINTR.
ERRORS
The pthread_spin_lock(),
pthread_spin_trylock() and
pthread_spin_unlock() functions will fail if:
- [
EINVAL] - The value specified by lock is invalid or is not initialized.
The pthread_spin_lock() function may fail
if:
- [
EDEADLK] - The calling thread already owns the lock.
The pthread_spin_trylock() function will
fail if:
- [
EBUSY] - Another thread currently holds lock.
The pthread_spin_unlock() function may
fail if:
- [
EPERM] - The calling thread does not own lock.
SEE ALSO
BUGS
The implementation of pthread_spin_lock(),
pthread_spin_trylock() and
pthread_spin_unlock() is expected to conform to
IEEE Std 1003.2 (“POSIX.2”).