pthread_spin_lock(3)

NAME

pthread_spin_lock, pthread_spin_trylock, pthread_spin_unlock

- lock or
unlock a spin lock

LIBRARY

library ``libpthread'' library ``libthr''

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

The pthread_spin_lock() function will acquire lock if it is

not currently
owned by another thread. If the lock cannot be acquired im

mediately, 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. Other

wise, 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 ini

tialized.

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

pthread_spin_destroy(3), pthread_spin_init(3)

HISTORY

The pthread_spin_lock(), pthread_spin_trylock() and

pthread_spin_unlock()
functions first appeared in library ``libpthread'' in FreeB

SD 5.2, and in
library ``libthr'' in FreeBSD 5.3.

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'').

BSD January 22, 2004

BSD