NetBSD/regress/lib/libpthread/once2/once2.c

62 lines
921 B
C

/* $NetBSD: once2.c,v 1.1 2003/01/30 19:32:00 thorpej Exp $ */
#include <assert.h>
#include <err.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
pthread_once_t once = PTHREAD_ONCE_INIT;
static int x;
#define NTHREADS 25
void ofunc(void);
void* threadfunc(void *);
int
main(int argc, char *argv[])
{
pthread_t threads[NTHREADS];
int id[NTHREADS];
int i;
printf("1: Test 2 of pthread_once()\n");
for (i=0; i < NTHREADS; i++) {
id[i] = i;
pthread_create(&threads[i], NULL, threadfunc, &id[i]);
}
for (i=0; i < NTHREADS; i++)
pthread_join(threads[i], NULL);
printf("1: X has value %d\n",x );
assert(x == 2);
return 0;
}
void
ofunc(void)
{
x++;
printf("ofunc: Variable x has value %d\n", x);
x++;
}
void *
threadfunc(void *arg)
{
int num;
pthread_once(&once, ofunc);
num = *(int *)arg;
printf("Thread %d sees x with value %d\n", num, x);
assert(x == 2);
return NULL;
}