• Start
• Documentation
  • PostgreSQL
  • mnoGoSearch
  • Apache 2.4
  • FreeBSD handbook
  • FreeBSD Manual
  • FreeBSD Source
• Tools
• Search
• Protected Area

plain

FreeBSD manual

keyword 1 2 3 4 5 6 7 8 9 n l

download PDF document: pthread_barrier_init.3.pdf

PTHREAD_BARRIER(3) FreeBSD Library Functions Manual PTHREAD_BARRIER(3)
NAME pthread_barrier_destroy, pthread_barrier_init, pthread_barrier_wait - destroy, initialize or wait on a barrier object
LIBRARY POSIX Threads Library (libpthread, -lpthread)
SYNOPSIS #include <pthread.h>
int pthread_barrier_destroy(pthread_barrier_t *barrier);
int pthread_barrier_init(pthread_barrier_t *restrict barrier, const pthread_barrierattr_t *attr, unsigned count);
int pthread_barrier_wait(pthread_barrier_t *barrier);
DESCRIPTION The pthread_barrier_init() function will initialize barrier with attributes specified in attr, or if it is NULL, with default attributes. The number of threads that must call pthread_barrier_wait() before any of the waiting threads can be released is specified by count. The pthread_barrier_destroy() function will destroy barrier and release any resources that may have been allocated on its behalf.
The pthread_barrier_wait() function will synchronize calling threads at barrier. The threads will be blocked from making further progress until a sufficient number of threads calls this function. The number of threads that must call it before any of them will be released is determined by the count argument to pthread_barrier_init(). Once the threads have been released the barrier will be reset.
IMPLEMENTATION NOTES In 1:1 Threading Library (libthr, -lthr) the PTHREAD_BARRIER_SERIAL_THREAD return value will always be returned by the last thread to reach the barrier.
RETURN VALUES If successful, both pthread_barrier_destroy() and pthread_barrier_init() will return zero. Otherwise, an error number will be returned to indicate the error. If the call to pthread_barrier_wait() is successful, all but one of the threads will return zero. That one thread will return PTHREAD_BARRIER_SERIAL_THREAD. Otherwise, an error number will be returned to indicate the error.
None of these functions will return EINTR.
ERRORS The pthread_barrier_destroy() function will fail if:
[EBUSY] An attempt was made to destroy barrier while it was in use.
The pthread_barrier_destroy() and pthread_barrier_wait() functions may initialize barrier.
[EINVAL] The count argument is less than 1.
[ENOMEM] Insufficient memory to initialize barrier.
SEE ALSO pthread_barrierattr(3)
HISTORY The pthread_barrier_destroy(), pthread_barrier_init() and pthread_barrier_wait() functions first appeared in N:M Threading Library (libkse, -lkse) in FreeBSD 5.2, and in 1:1 Threading Library (libthr, -lthr) in FreeBSD 5.3.
FreeBSD 14.0-RELEASE-p6 August 17, 2018 FreeBSD 14.0-RELEASE-p6