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PTHREAD_BARRIER_DESTROY(3P)OSIX Programmer's ManualHREAD_BARRIER_DESTROY(3P)
This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior), or
the interface may not be implemented on Linux.
pthread_barrier_destroy, pthread_barrier_init — destroy and
initialize a barrier object
#include <pthread.h>
int pthread_barrier_destroy(pthread_barrier_t *barrier);
int pthread_barrier_init(pthread_barrier_t *restrict barrier,
const pthread_barrierattr_t *restrict attr, unsigned count);
The pthread_barrier_destroy() function shall destroy the barrier
referenced by barrier and release any resources used by the barrier.
The effect of subsequent use of the barrier is undefined until the
barrier is reinitialized by another call to pthread_barrier_init().
An implementation may use this function to set barrier to an invalid
value. The results are undefined if pthread_barrier_destroy() is
called when any thread is blocked on the barrier, or if this function
is called with an uninitialized barrier.
The pthread_barrier_init() function shall allocate any resources
required to use the barrier referenced by barrier and shall
initialize the barrier with attributes referenced by attr. If attr
is NULL, the default barrier attributes shall be used; the effect is
the same as passing the address of a default barrier attributes
object. The results are undefined if pthread_barrier_init() is called
when any thread is blocked on the barrier (that is, has not returned
from the pthread_barrier_wait() call). The results are undefined if a
barrier is used without first being initialized. The results are
undefined if pthread_barrier_init() is called specifying an already
initialized barrier.
The count argument specifies the number of threads that must call
pthread_barrier_wait() before any of them successfully return from
the call. The value specified by count must be greater than zero.
If the pthread_barrier_init() function fails, the barrier shall not
be initialized and the contents of barrier are undefined.
Only the object referenced by barrier may be used for performing
synchronization. The result of referring to copies of that object in
calls to pthread_barrier_destroy() or pthread_barrier_wait() is
undefined.
Upon successful completion, these functions shall return zero;
otherwise, an error number shall be returned to indicate the error.
The pthread_barrier_init() function shall fail if:
EAGAIN The system lacks the necessary resources to initialize another
barrier.
EINVAL The value specified by count is equal to zero.
ENOMEM Insufficient memory exists to initialize the barrier.
These functions shall not return an error code of [EINTR].
The following sections are informative.
None.
None.
If an implementation detects that the value specified by the barrier
argument to pthread_barrier_destroy() does not refer to an
initialized barrier object, it is recommended that the function
should fail and report an [EINVAL] error.
If an implementation detects that the value specified by the attr
argument to pthread_barrier_init() does not refer to an initialized
barrier attributes object, it is recommended that the function should
fail and report an [EINVAL] error.
If an implementation detects that the value specified by the barrier
argument to pthread_barrier_destroy() or pthread_barrier_init()
refers to a barrier that is in use (for example, in a
pthread_barrier_wait() call) by another thread, or detects that the
value specified by the barrier argument to pthread_barrier_init()
refers to an already initialized barrier object, it is recommended
that the function should fail and report an [EBUSY] error.
None.
pthread_barrier_wait(3p)
The Base Definitions volume of POSIX.1‐2008, pthread.h(0p)
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information
Technology -- Portable Operating System Interface (POSIX), The Open
Group Base Specifications Issue 7, Copyright (C) 2013 by the
Institute of Electrical and Electronics Engineers, Inc and The Open
Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
applied.) 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.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the
source files to man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 PTHREAD_BARRIER_DESTROY(3P)
Pages that refer to this page: pthread.h(0p), pthread_barrierattr_getpshared(3p), pthread_barrier_wait(3p)