还以为线程没运行不运行

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <errno.h>
 
 
 
pthread_cond_t cond_a;
pthread_cond_t cond_b;
pthread_cond_t cond_c;

pthread_mutex_t lock_a; 
pthread_mutex_t lock_b; 
pthread_mutex_t lock_c; 
 
void * funa(void *arg)
{
    int i;
    for(i = 0; i<10;i++)
    {
        if ( pthread_mutex_lock(&lock_a))
        {
            printf("lock failure\n");
            exit(0);
        }
        printf("A[%d]\n", i);        
        if ( pthread_cond_signal(&cond_b))
        {
            printf("lock failure\n");
            exit(0);
        }
        
        if ( pthread_cond_wait(&cond_a, &lock_a))
        {
            printf("lock failure\n");
            exit(0);
        }
        
        if (pthread_mutex_unlock(&lock_a))
        {
            printf("lock failure\n");
            exit(0);
        }
    
    }
    
    printf("A exit\n");
    pthread_exit(NULL);
}

void * funb(void *arg)
{
    int i;
    for(i = 0; i<10;i++)
    {
        if ( pthread_mutex_lock(&lock_b))
        {
            printf("lock failure\n");
            exit(0);
        }
        printf("B[%d]", i);        
        if ( pthread_cond_signal(&cond_c))
        {
            printf("lock failure\n");
            exit(0);
        }
        
        if ( pthread_cond_wait(&cond_b, &lock_b))
        {
            printf("lock failure\n");
            exit(0);
        }
        
        if (pthread_mutex_unlock(&lock_b))
        {
            printf("lock failure\n");
            exit(0);
        }
        
    }
    printf("A exit\n");
    pthread_exit(NULL);
}

void * func(void *arg)
{
    int i;
    for(i = 0; i<10;i++)
    {
        if ( pthread_mutex_lock(&lock_c))
        {
            printf("lock failure\n");
            exit(0);
        }
        printf("C[%d]", i);        
        if ( pthread_cond_signal(&cond_a))
        {
            printf("lock failure\n");
            exit(0);
        }
        
        if ( pthread_cond_wait(&cond_c, &lock_c))
        {
            printf("lock failure\n");
            exit(0);
        }
        
        if (pthread_mutex_unlock(&lock_c))
        {
            printf("lock failure\n");
            exit(0);
        }    
    }
    printf("A exit\n");
    pthread_exit(NULL);
}




int main(int argc, char *argv[])
{
 
    pthread_t ta,tb,tc;
    int ret;
    int i;
    pthread_mutex_init(&lock_a, NULL);
    pthread_mutex_init(&lock_b, NULL);
    pthread_mutex_init(&lock_c, NULL);
    pthread_cond_init(&cond_a, NULL);
    pthread_cond_init(&cond_b, NULL);
    pthread_cond_init(&cond_c, NULL);

    ret = pthread_create(&ta, NULL, funa, (void*)1);
    if(ret)
    {
        printf("pthread_create ta error [%s]", strerror(errno));
        return 1;
    }
    ret = pthread_create(&tb, NULL, funb, (void*)2);
    if(ret)
    {
        printf("pthread_create tb error [%s]", strerror(errno));
        return 1;
    }
    ret = pthread_create(&tc, NULL, func, (void*)3);
    if(ret)
    {
        printf("pthread_create tc error [%s]", strerror(errno));
        return 1;
    }
    
 

    pthread_join(ta, NULL);
    pthread_join(tb, NULL);
    pthread_join(tc, NULL);
    pthread_cond_destroy(&cond_a);
    pthread_cond_destroy(&cond_b);
    pthread_cond_destroy(&cond_c);
    pthread_mutex_destroy(&lock_a);
    pthread_mutex_destroy(&lock_b);
    pthread_mutex_destroy(&lock_c);
    printf("\nmain thread exit\n");
    return 0;
}