pthread_once

PTHREAD_ONCE(3)             Library Functions Manual             PTHREAD_ONCE(3)



NAME
       pthread_once - once-only initialization


SYNOPSIS
       #include <pthread.h>

       pthread_once_t once_control = PTHREAD_ONCE_INIT;

       int pthread_once(pthread_once_t *once_control, void (*init_routine)
       (void));


DESCRIPTION
       The purpose of pthread_once is to ensure that a piece of initialization
       code is executed at most once. The once_control argument points to a
       static or extern variable statically initialized to PTHREAD_ONCE_INIT.

       The first time pthread_once is called with a given once_control argument,
       it calls init_routine with no argument and changes the value of the
       once_control variable to record that initialization has been performed.
       Subsequent calls to pthread_once with the same once_control argument do
       nothing.


RETURN VALUE
       pthread_once always returns 0.


ERRORS
       None.


AUTHOR
       Xavier Leroy <Xavier.Leroy@inria.fr>




                                  LinuxThreads                   PTHREAD_ONCE(3)