PTHREAD_SPIN_DESTROY(3C)PTHREAD_SPIN_DESTROY(3C)NAME
pthread_spin_destroy, pthread_spin_init - destroy or initialize a spin
lock object
SYNOPSIS
cc -mt [ flag... ] file... [ library... ]
#include <pthread.h>
int pthread_spin_destroy(pthread_spinlock_t *lock);
int pthread_spin_init(pthread_spinlock_t *lock, int pshared);
DESCRIPTION
The pthread_spin_destroy() function destroys the spin lock referenced
by lock and release any resources used by the lock. The effect of sub‐
sequent use of the lock is undefined until the lock is reinitialized by
another call to pthread_spin_init(). The results are undefined if
pthread_spin_destroy() is called when a thread holds the lock, or if
this function is called with an uninitialized thread spin lock.
The pthread_spin_init() function allocates any resources required to
use the spin lock referenced by lock and initialize the lock to an
unlocked state.
If the Thread Process-Shared Synchronization option is supported and
the value of pshared is PTHREAD_PROCESS_SHARED, the spin lock can be
operated upon by any thread that has access to the memory where the
spin lock is allocated, even if it is allocated in memory that is
shared by multiple processes.
If the Thread Process-Shared Synchronization option is supported and
the value of pshared is PTHREAD_PROCESS_PRIVATE, or if the option is
not supported, the spin lock can only be operated upon by threads cre‐
ated within the same process as the thread that initialized the spin
lock. If threads of differing processes attempt to operate on such a
spin lock, the behavior is undefined.
The results are undefined if pthread_spin_init() is called specifying
an already initialized spin lock. The results are undefined if a spin
lock is used without first being initialized.
If the pthread_spin_init() function fails, the lock is not initialized
and the contents of lock are undefined.
Only the object referenced by lock can be used for performing synchro‐
nization.
The result of referring to copies of that object in calls to
pthread_spin_destroy(), pthread_spin_lock(3C), pthread_spin_try‐
lock(3C), or pthread_spin_unlock(3C) is undefined.
RETURN VALUES
Upon successful completion, these functions returns 0. Otherwise, an
error number is returned to indicate the error.
ERRORS
The pthread_spin_init() function will fail if:
EAGAIN
The system lacks the necessary resources to initialize
another spin lock.
These functions may fail if:
EBUSY
The system has detected an attempt to initialize or destroy a
spin lock while it is in use (for example, while being used
in a pthread_spin_lock() call) by another thread.
EINVAL
The value specified by lock is invalid.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌────────────────────┬─────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├────────────────────┼─────────────────┤
│Interface Stability │ Standard │
├────────────────────┼─────────────────┤
│MT-Level │ MT-Safe │
└────────────────────┴─────────────────┘
SEE ALSOpthread_spin_lock(3C), pthread_spin_unlock(3C), attributes(5), stan‐
dards(5)
Jan 30, 2004 PTHREAD_SPIN_DESTROY(3C)