pthread_once

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>