NAME
sem_destroy - destroy an unnamed semaphore (REALTIME)
SYNOPSIS
#include <semaphore.h>
int sem_destroy(sem_t *sem);
DESCRIPTION
The sem_destroy() function shall destroy the unnamed semaphore
indicated by sem. Only a semaphore that was created using sem_init()
may be destroyed using sem_destroy(); the effect of calling
sem_destroy() with a named semaphore is undefined. The effect of
subsequent use of the semaphore sem is undefined until sem is
reinitialized by another call to sem_init().
It is safe to destroy an initialized semaphore upon which no threads
are currently blocked. The effect of destroying a semaphore upon which
other threads are currently blocked is undefined.
RETURN VALUE
Upon successful completion, a value of zero shall be returned.
Otherwise, a value of -1 shall be returned and errno set to indicate
the error.
ERRORS
The sem_destroy() function shall fail if:
EINVAL The sem argument is not a valid semaphore.
The sem_destroy() function may fail if:
EBUSY There are currently processes blocked on the semaphore.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
The sem_destroy() function is part of the Semaphores option and need
not be available on all implementations.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
semctl() , semget() , semop() , sem_init() , sem_open() , the Base
Definitions volume of IEEE Std 1003.1-2001, <semaphore.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online
at http://www.opengroup.org/unix/online.html .