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)