互斥锁和条件变量
// //模拟黄牛抢票，100张票，共有四个黄牛在抢票
// #include <stdio.h>
// #include <errno.h>
// #include <unistd.h>
// #include <stdlib.h>
// #include <pthread.h>// int ticket = 100;
// pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;//定义初始化锁// void* thr_start(void* arg){
// while(1){
// pthread_mutex_lock(&mutex);
// if(ticket > 0){
// usleep(1);
// printf("yellow bull : %d----get ticket : %d\n",(int)arg,ticket);
// ticket--;
// }else{
// pthread_mutex_unlock(&mutex);
// pthread_exit(NULL);
// }
// pthread_mutex_unlock(&mutex);
// }
// return NULL;
// }// int main(int argc, char* argv[]){
// pthread_t tid[4];
// int i = 0,ret;// pthread_mutex_init(&mutex,NULL);
// for(;i < 4; ++i){
// ret = pthread_create(&tid[i],NULL,thr_start,(void*)i);
// printf("jj=%d\n",i);
// //pthread_join(tid[i],NULL);
// if(ret != 0){
// printf("yellow bull no exit!");
// return -1;
// }
// }
// for(i = 0;i < 4;++i){
// pthread_join(tid[i],NULL);
// printf("jyyyj=%d\n",i);
// }
// pthread_mutex_destroy(&mutex);
// return 0;
// }//模拟一个skr与cxk使用比赛舞台的Demo #include <stdio.h> #include <pthread.h> #include <unistd.h> #include <errno.h> #include <stdlib.h> int have_stage = 1; pthread_cond_t skr; pthread_cond_t cxk; pthread_mutex_t mutex; void* thr_skr(void* arg){//skr此时要上台dancing while(1){ pthread_mutex_lock(&mutex); //若此时舞台有人用，那么skr进行等待 while(have_stage == 1){ pthread_cond_wait(&skr,&mutex); //满足条件，线程等待。会自动释放锁} //舞台被人使用了，此时0；因为之前1，代表可以使用 printf("skr~~ is freestyle!!!\n"); sleep(1); //跳完舞后舞台空了出来 have_stage += 1; //有舞台了，叫cxk来使用 pthread_cond_signal(&cxk); pthread_mutex_unlock(&mutex);}return NULL;}void* thr_cxk(void* arg){while(1){pthread_mutex_lock(&mutex);//没有舞台，那么在这里等待while(have_stage == 0){pthread_cond_wait(&cxk,&mutex);}//有了舞台就是可以唱跳rap篮球了。。printf("cxk~~ is singing,dancing,playing rapping and basketball!!\n");sleep(1);have_stage -= 1;//跳完还想跳。。因此叫skr快跳完换他跳。。pthread_mutex_unlock(&mutex);pthread_cond_signal(&skr);//唤醒skr，}return NULL;} int main(int argc,char * argv[]){pthread_t tid1,tid2;int ret;pthread_cond_init(&skr,NULL);pthread_cond_init(&cxk,NULL);pthread_mutex_init(&mutex,NULL);int i = 0;//for(i = 0;i < 2;i++){ret = pthread_create(&tid1,NULL,thr_skr,NULL);if(ret != 0){printf("skr error");return -1;}//}//for(i = 0;i < 2; i++){ret = pthread_create(&tid2,NULL,thr_cxk,NULL);if(ret != 0){printf("cxk error");return -1;}//}pthread_join(tid1,NULL);pthread_join(tid2,NULL);pthread_cond_destroy(&skr);pthread_cond_destroy(&cxk);pthread_mutex_destroy(&mutex);return 0;}
信号量
/*#########################################################
多线程开发的最基本概念主要包含四点：线程，互斥锁，条件变量、读写锁。
其中，线程操作又分线程的创建，退出，等待 3 种。
互斥锁则包括 4 种操作，分别是创建，销毁，加锁和解锁。
条件操作有 5 种操作：创建，销毁，触发，广播和等待
##########################################################*/// #include <stdio.h>
// #include <pthread.h>
// #include <unistd.h>
// #include <string.h>// void print_message_func(void *ptr);// int main()
// {
// int tmp1,tmp2;
// void *retival;
// pthread_t thread1,thread2;
// char *message1 = "thread1";
// char *message2 = "thread2";// int ret_thread1,ret_thread2;
// ret_thread1 = pthread_create(&thread1,NULL,(void *)&print_message_func,(void *)message1);// if(ret_thread1 == 0)
// printf("create thread 1 true\n");
// else
// printf("create thread 1 false\n");// tmp1 = pthread_join(thread1,&retival);
// printf("thread 1 return value (tmp1) is %d\n",tmp1);// if(tmp1 != 0)
// printf("cannot join with thread 1\n");// ret_thread2 = pthread_create(&thread2,NULL,(void *)&print_message_func,(void *)message2);// if(ret_thread2 == 0)
// printf("create thread 2 true\n");
// else
// printf("create thread 2 false\n");// tmp2 = pthread_join(thread2,&retival);
// printf("thread 2 return value (tmp2) is %d\n",tmp2);
// if(tmp2 != 0)
// printf("cannot join with thread 2\n");
// }// void print_message_func(void *ptr)
// {
// for(int i=0;i<5;++i)
// {
// printf("%s:%d\n",(char *)ptr,i); //强制类型转换
// }
// }// #include <stdio.h>
// #include <stdlib.h>
// #include <pthread.h>// int sharei = 0;
// void increase_num(void);// pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;//初始化锁位解锁状态// int main()
// {
// int ret;
// pthread_t thread1,thread2,thread3;
// ret = pthread_create(&thread1,NULL,(void *)&increase_num,NULL);
// ret = pthread_create(&thread2,NULL,(void *)&increase_num,NULL);
// ret = pthread_create(&thread3,NULL,(void *)&increase_num,NULL);// pthread_join(thread1,NULL);
// pthread_join(thread2,NULL);
// pthread_join(thread3,NULL);// printf("sharei = %d\n",sharei);// return 0;
// }// void increase_num(void)
// {
// long i,tmp;
// for(i =0;i<=10000;++i)
// {// if(pthread_mutex_lock(&mutex) !=0)//（阻塞加锁）访问临界区加锁操作
// {
// perror("pthread_mutex_lock");
// exit(EXIT_FAILURE);
// }// tmp = sharei;
// tmp = tmp + 1;
// sharei = tmp;// if(pthread_mutex_unlock(&mutex) !=0)//访问临界区解锁操作
// {
// perror("pthread_mutex_unclock");
// exit(EXIT_FAILURE);
// }
// }
// }/*#########################################################################int sem_init(sem_t * sem, int pshared, unsigned int value);初始化信号量- 成功返回0，失败返回-1；- 参数sem：表示指向信号结构的指针。- 参数pshared：不是0 的时候该信号量在进程间共享，否则只能在当前进程的所有线程间共享。- 参数value：信号量的初始值。int sem_wait(sem_t *sem); 信号量减一操作，有线程申请资源- 成功返回0，否则返回-1- 参数sem：指向一个信号量的指针int sem_post(sem_t *sem); 信号量加一操作，有线程释放资源- 成功返回0，否则返回-1- 参数sem：指向一个信号量指针int sem_destroy(sem_t *sem); 销毁信号量。- 成功返回0，否则返回-1- 参数sem：指向一个信号量的指针。########################################################################*/
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <semaphore.h>#define MAXSIZE 10int stack[MAXSIZE];int size =0;
sem_t sem;void privide_data(void){int i;for(i =0;i<MAXSIZE;++i){stack[i] = i;printf("%d\n",stack[i]);sem_post(&sem);//信号量加1，释放资源//printf("%d",stack[i]);}}void handle_data(void)
{int i;while((i = size ++) <MAXSIZE){sem_wait(&sem);//信号量减一，申请资源printf("cross : %d X %d = %d \n",stack[i],stack[i],stack[i] * stack[i]);sleep(1);}
}int main()
{pthread_t privider,handler;sem_init(&sem,0,0);pthread_create(&privider,NULL,(void *)&privide_data,NULL);pthread_create(&handler,NULL,(void *)&handle_data,NULL);pthread_join(privider,NULL);//pthread_join(handler,NULL);sem_destroy(&sem);return 0;
}