pthread_once
#define _PROP_ONCE_RUN(x,f) pthread_once(&(x),(void(*)(void))f)
pthread_once(once_control, init_routine);
pthread_once(&tm_multi_once, tm_multi_key_init);
(void)pthread_once(flag, func);
int pthread_once(pthread_once_t *, void (*)(void));
__strong_alias(__libc_thr_once,pthread_once)
PTHREAD_REQUIRE(pthread_once(&once, once3_ofunc));
PTHREAD_REQUIRE(pthread_once(&once, ofunc));
(void)pthread_once(&once, &ofunc_silent);
(void)pthread_once(&once, &ofunc_silent);
PTHREAD_REQUIRE(pthread_once(&once, ofunc));
PTHREAD_REQUIRE(pthread_once(&once, ofunc));
PTHREAD_REQUIRE(pthread_once(&once, once2_ofunc));