Files
ostep-code/threads-cv/join_no_lock.c
Remzi Arpaci-Dusseau 0e2552ac55 no lock while signalling
2019-04-30 09:57:31 -05:00

35 lines
734 B
C

#include <stdio.h>
#include <unistd.h>
#include <pthread.h>
#include "common.h"
#include "common_threads.h"
pthread_cond_t c = PTHREAD_COND_INITIALIZER;
pthread_mutex_t m = PTHREAD_MUTEX_INITIALIZER;
int done = 0;
void *child(void *arg) {
printf("child: begin\n");
sleep(1);
done = 1;
printf("child: signal\n");
Cond_signal(&c);
return NULL;
}
int main(int argc, char *argv[]) {
pthread_t p;
printf("parent: begin\n");
Pthread_create(&p, NULL, child, NULL);
Mutex_lock(&m);
printf("parent: check condition\n");
while (done == 0) {
sleep(2);
printf("parent: wait to be signalled...\n");
Cond_wait(&c, &m);
}
Mutex_unlock(&m);
printf("parent: end\n");
return 0;
}