pthread_once.3t (2010 09)

pthread_once(3T) pthread_once(3T)

(Pthread Library)

For a multithreaded process, a simple initialization ﬂag is not sufﬁcient; the ﬂag must be protected

against modiﬁcation by multiple threads. Consequently, this ﬂag has to be protected by a mutex that has

to be initialized only once, and so on. A multithreaded program should use initialization similar to:

static pthread_once_t once_control = PTHREAD_ONCE_INIT;

extern void initialize();

(void)pthread_once(&once_control, initialize);

(Rest of the code after initialization.)

AUTHOR

pthread_once()

was derived from the IEEE POSIX P1003.1c standard.