pthread_once(3) — Linux manual page

NAME \| SYNOPSIS \| DESCRIPTION \| RETURN VALUE \| ERRORS \| COLOPHON

pthread_once(3)         Library Functions Manual         pthread_once(3)

NAME top

       pthread_once - once-only initialization

SYNOPSIS top

       #include <pthread.h>

       pthread_once_t once_control = PTHREAD_ONCE_INIT;

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

DESCRIPTION top

       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 top

       pthread_once always returns 0.

ERRORS top

       None.

COLOPHON top

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Linux man-pages 6.9.1          2024-05-02                pthread_once(3)

Pages that refer to this page: pthreads(7)