1. 编写一个基本的多线程程序（主线程里面创建一个子线程）
/*************************************************************************> File Name: 1_homework.c> Author: 梁惠涌> Addr: > Created Time: 2015年04月22日 星期三 15时22分34秒 ************************************************************************/#include<stdio.h>#include<stdlib.h>#include<string.h>#include<unistd.h>#include<pthread.h>#include <semaphore.h> //sem_t 的声明void *fun1(void *arg){pthread_detach( pthread_self() );//与主线程分离while(1){*((int *)arg) += 2;printf("fun1 the num is: %d \n",*((int*)arg));sleep(1);}pthread_exit(0);//主线程结束}int main(){int num=3, ret1;pthread_t thread1;ret1 = pthread_create(&thread1, NULL, fun1, (void *)&num);if(ret1 != 0){perror("pthread_create1");exit(0);}sleep(1);printf("=================== main end ================\n");pthread_exit(0);//主线程结束}
2. 把上面的程序改为子线程给父线程传递返回值
/*************************************************************************> File Name: 2_homework.c> Author: 梁惠涌> Addr:> Created Time: 2015年04月22日 星期三 15时39分49秒 ************************************************************************/#include<stdio.h>#include<stdlib.h>#include<string.h>#include<unistd.h>#include<pthread.h>void *fun1(void *arg){int num=100;printf("—————pthread————–\n");printf("the num is: %d \n", num);printf("————— end ————–\n");pthread_exit((void *)num);//主线程结束}int main(){int ret1, num;pthread_t thread1;ret1 = pthread_create(&thread1, NULL, fun1, NULL);if(ret1 != 0){perror("pthread_create1");exit(0);}pthread_join(thread1,(void *)&num);printf("————— main ————–\n");printf("return the num is: %d \n", (int )num);printf("————— end ————–\n");pthread_exit(0);//主线程结束}
3. 用多线程写一个程序，实现对数据的读写（可以是一个全局变量或其他的数据）
/*************************************************************************> File Name: 3_homework.c> Author: 梁惠涌> Addr: > Created Time: 2015年04月22日 星期三 15时53分00秒 ************************************************************************/#include<stdio.h>#include<stdlib.h>#include<string.h>#include<unistd.h>#include<pthread.h>#include <semaphore.h> //sem_t 的声明void *fun1(void *arg){pthread_detach( pthread_self() );//与主线程分离while(1){*((int *)arg) += 2;printf("the num write: %d \n",*((int*)arg));sleep(1);}pthread_exit(0);//主线程结束}void *fun2(void *arg){pthread_detach( pthread_self() );//与主线程分离while(1){printf("the num read is: %d \n",*((int*)arg));sleep(1);}pthread_exit(0);//主线程结束}int main(){int num=0, ret1;pthread_t thread1, thread2;ret1 = pthread_create(&thread1, NULL, fun1, (void *)&num);if(ret1 != 0){perror("pthread_create1");exit(0);}ret1 = pthread_create(&thread2, NULL, fun2, (void *)&num);if(ret1 != 0){perror("pthread_create2");exit(0);}sleep(1);printf("=================== main end ================\n");pthread_exit(0);//主线程结束}
4. 分别用信号量和互斥锁实现第3个作业的读写互斥
/*************************************************************************> File Name: 4_homework.c> Author: 梁惠涌> Addr:> Created Time: 2015年04月22日 星期三 15时57分54秒 ************************************************************************/#include<stdio.h>#include<stdlib.h>#include<string.h>#include<unistd.h>#include<pthread.h>#include <semaphore.h> //sem_t 的声明sem_t sem;//信号量声明pthread_mutex_t mutex; //互斥锁声明void *fun1(void *arg){pthread_detach( pthread_self() );//与主线程分离while(1){sem_wait(&sem);*((int *)arg) += 2;printf("==信号量== num write: %d \n",*((int*)arg));sleep(1);sem_post(&sem);}pthread_exit(0);//主线程结束}void *fun2(void *arg){pthread_detach( pthread_self() );//与主线程分离while(1){sem_wait(&sem);printf("==信号量== num read is: %d \n",*((int*)arg));sleep(1);sem_post(&sem);}pthread_exit(0);//主线程结束}void *fun3(void *arg){pthread_detach( pthread_self() );//与主线程分离while(1){pthread_mutex_lock(&mutex);*((int *)arg) += 2;printf(">>互斥锁>> num write: %d \n",*((int*)arg));sleep(1);pthread_mutex_unlock(&mutex);}pthread_exit(0);//主线程结束}void *fun4(void *arg){pthread_detach( pthread_self() );//与主线程分离while(1){pthread_mutex_lock(&mutex);printf(">>互斥锁>> num read is: %d \n",*((int*)arg));sleep(1);pthread_mutex_unlock(&mutex);}pthread_exit(0);//主线程结束}int main(){//————————信号量互斥——————–int num1=0, ret1;pthread_t thread1, thread2;sem_init(&sem, 0, 1);ret1 = pthread_create(&thread1, NULL, fun1, (void *)&num1);if(ret1 != 0){perror("pthread_create1");exit(0);}ret1 = pthread_create(&thread2, NULL, fun2, (void *)&num1);if(ret1 != 0){perror("pthread_create2");exit(0);}//————————互斥锁互斥——————–int num2=1000, ret2;pthread_t thread_1, thread_2;pthread_mutex_init(&mutex, NULL);ret2 = pthread_create(&thread_1, NULL, fun3, (void *)&num2);if(ret2!= 0){perror("pthread_create1");exit(0);}ret1 = pthread_create(&thread_2, NULL, fun4, (void *)&num2);if(ret2 != 0){perror("pthread_create2");exit(0);}printf("=================== main end ================\n");pthread_exit(0);//主线程结束}
5. 用信号量实现第3个作业的读写同步
当一个人把寂寞当作人生预约的美丽，
