将信号指向C中的特定线程

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>

pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
int ready = 0;

void* worker(void* arg) {
    int thread_id = *(int*)arg;
    pthread_mutex_lock(&mutex);
    while (ready == 0) {
        pthread_cond_wait(&cond, &mutex);
    }
    pthread_mutex_unlock(&mutex);
    printf("Thread %d received the signal\n", thread_id);
    return NULL;
}

int main() {
    pthread_t threads[5];
    int thread_ids[5] = {1, 2, 3, 4, 5};

    for (int i = 0; i < 5; i++) {
        pthread_create(&threads[i], NULL, worker, &thread_ids[i]);
    }

    sleep(1); // 等待线程启动

    pthread_mutex_lock(&mutex);
    ready = 1;
    pthread_cond_broadcast(&cond); // 发送信号给所有等待的线程
    pthread_mutex_unlock(&mutex);

    for (int i = 0; i < 5; i++) {
        pthread_join(threads[i], NULL);
    }

    pthread_mutex_destroy(&mutex);
    pthread_cond_destroy(&cond);

    return 0;
}