#include <pthread.h> #include <stdio.h> pthread_once_t once = PTHREAD_ONCE_INIT; void myfunc(void) { printf("only see this once\n"); } void * mythread(void * arg) { int rc = pthread_once(&once, myfunc); printf("returned %d\n", rc); return 0; } int main() { int rc; pthread_t t1, t2; rc = pthread_create(&t1, NULL, mythread, NULL); printf("pthread_create returned %d\n", rc); rc = pthread_create(&t2, NULL, mythread, NULL); printf("pthread_create returned %d\n", rc); Sleep(2000); return 0; }