shell实现中管道命令执行之间的竞争条件

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

int shared_data = 0;
pthread_mutex_t mutex;

void* thread_func(void* arg) {
    pthread_mutex_lock(&mutex);  // 获取互斥锁
    shared_data++;
    printf("Thread %d: shared_data = %d\n", *(int*)arg, shared_data);
    pthread_mutex_unlock(&mutex);  // 释放互斥锁
    return NULL;
}

int main() {
    pthread_t thread1, thread2;

    pthread_mutex_init(&mutex, NULL);  // 初始化互斥锁

    int thread1_id = 1;
    int thread2_id = 2;

    pthread_create(&thread1, NULL, thread_func, &thread1_id);
    pthread_create(&thread2, NULL, thread_func, &thread2_id);

    pthread_join(thread1, NULL);
    pthread_join(thread2, NULL);

    pthread_mutex_destroy(&mutex);  // 销毁互斥锁

    return 0;
}