2024.2.22

将互斥机制的代码实现

#include<myhead.h>
int num=7;
pthread_mutex_t mutex;//创建互斥锁变量
void *task1(void *arg)
{
	printf("task1:\n");
	//获取锁资源
	pthread_mutex_lock(&mutex);
	num=77777;
	sleep(2);
printf("task1:num=%d\n",num);
//释放锁资源
pthread_mutex_unlock(&mutex);
}
void *task2(void *arg)
{
	printf("task2:\n");
	//获取锁资源
	pthread_mutex_lock(&mutex);
	num=num+1;
	sleep(1);
printf("task2:num=%d\n",num);
//释放锁资源
pthread_mutex_unlock(&mutex);
}
int main(int argc, const char *argv[])
{
	//初始化互斥锁
	pthread_mutex_init(&mutex,NULL);
	//创建线程
	pthread_t tid1,tid2;
	if(pthread_create(&tid1,NULL,task1,NULL)!=0)
	{
		printf("tid1 creat error");
		return 0;
	}
	if(pthread_create(&tid2,NULL,task2,NULL)!=0)
	{
		printf("tid2 creat error");
		return 0;
	}
	//回收线程资源
	pthread_join(tid1,NULL);
	pthread_join(tid2,NULL);
	//销毁锁资源
	pthread_mutex_destroy(&mutex);

return 0;
}

将无名信号量的代码实现重新敲一遍

#include<myhead.h>
sem_t sem1;//创建无名信号量1

void *task1(void *arg)
{
	int num=5;
	while(num--)
	{
		printf("我生产了\n");
	sem_post(&sem1);//释放资源
	}
	pthread_exit(NULL);//退出线程
}
void *task2(void *arg)
{
	int num=5;
	while(num--)
	{
		//申请资源
		sem_wait(&sem1);
			printf("我消费了\n");
		
	}
	pthread_exit(NULL);//退出线程
}
int main(int argc, const char *argv[])
{
	//初始化无名信号量
	sem_init(&sem1,0,0);
	pthread_t pid1,pid2;
	if(pthread_create(&pid1,NULL,task1,NULL)!=0)
	{
		printf("pid1 create error\n");
		return 0;
	}
	if(pthread_create(&pid2,NULL,task2,NULL)!=0)
	{
		printf("pid2 create error\n");
		return 0;
	}
	pthread_join(pid1,NULL);
	pthread_join(pid2,NULL);
	sem_destroy(&sem1);
return 0;
}

将条件变量的代码实现重新敲一遍

#include<myhead.h>
pthread_cond_t cond;
pthread_mutex_t mutex;
void *task1(void *arg)
{
	int num=5;
	while(num--)
	{
		sleep(1);
		printf("%#lx:生产了一个\n",pthread_self());
		pthread_cond_signal(&cond);
	}
	pthread_exit(NULL);
}
void *task2(void *arg)
{
	pthread_mutex_lock(&mutex);
	pthread_cond_wait(&cond,&mutex);
		printf("%#lx:消费了一个\n",pthread_self());
		pthread_mutex_unlock(&mutex);
	pthread_exit(NULL);
}

int main(int argc, const char *argv[])
{
	//初始化条件变量
	pthread_cond_init(&cond,NULL);
	//初始化互斥锁
	pthread_mutex_init(&mutex,NULL);
	//创建线程
	pthread_t tid1,tid2,tid3,tid4,tid5,tid6;
	if(pthread_create(&tid1,NULL,task1,NULL)!=0)
	{
	printf("tid1 create error\n");
	return 0;
	}
if(pthread_create(&tid2,NULL,task2,NULL)!=0)
	{
	printf("tid1 create error\n");
	return 0;
	}
if(pthread_create(&tid3,NULL,task2,NULL)!=0)
	{
	printf("tid1 create error\n");
	return 0;
	}
if(pthread_create(&tid4,NULL,task2,NULL)!=0)
	{
	printf("tid1 create error\n");
	return 0;
	}
if(pthread_create(&tid5,NULL,task2,NULL)!=0)
	{
	printf("tid1 create error\n");
	return 0;
	}
if(pthread_create(&tid6,NULL,task2,NULL)!=0)
	{
	printf("tid1 create error\n");
	return 0;
	}
pthread_join(tid1,NULL);
pthread_join(tid2,NULL);
pthread_join(tid3,NULL);
pthread_join(tid4,NULL);
pthread_join(tid5,NULL);
pthread_join(tid6,NULL);
pthread_cond_destroy(&cond);
pthread_mutex_destroy(&mutex);

return 0;
}

将无名管道的代码实现重新敲一遍

#include<myhead.h>
sem_t sem1;//创建无名信号量1

void *task1(void *arg)
{
	int num=5;
	while(num--)
	{
		printf("我生产了\n");
	sem_post(&sem1);//释放资源
	}
	pthread_exit(NULL);//退出线程
}
void *task2(void *arg)
{
	int num=5;
	while(num--)
	{
		//申请资源
		sem_wait(&sem1);
			printf("我消费了\n");
		
	}
	pthread_exit(NULL);//退出线程
}
int main(int argc, const char *argv[])
{
	//初始化无名信号量
	sem_init(&sem1,0,0);
	pthread_t pid1,pid2;
	if(pthread_create(&pid1,NULL,task1,NULL)!=0)
	{
		printf("pid1 create error\n");
		return 0;
	}
	if(pthread_create(&pid2,NULL,task2,NULL)!=0)
	{
		printf("pid2 create error\n");
		return 0;
	}
	pthread_join(pid1,NULL);
	pthread_join(pid2,NULL);
	sem_destroy(&sem1);
return 0;
}

将有名管道的代码实现重新敲一遍

name_creat.c

#include<myhead.h>
int main(int argc, const char *argv[])
{
	//创建管道
	if(mkfifo("./myfifo",0664)==-1)
	{
		perror("mkfifo error");
		return -1;
	}
	getchar();//阻塞
	system("rm myfifo");
return 0;
}


 write_namepipe.c 

#include<myhead.h>
int main(int argc, const char *argv[])
{
	//打开管道
	int wfd=-1;
	//只写打开文件
	if((wfd=open("./myfifo",O_WRONLY))==-1)
	{
		perror("open error");
		return -1;
	}
	//定义容器
	char wbuf[128]="";
	while(1)
	{
		printf("please input:\n");
		fgets(wbuf,sizeof(wbuf),stdin);
		wbuf[strlen(wbuf)-1]=0;
		//将数据写入管道
		write(wfd,wbuf,strlen(wbuf));
		//判断是否退出
		if(strcmp(wbuf,"quit")==0)
		{
			break;
		}
 		close(wfd);
		return 0;
	}

return 0;
}

read_namepipe.c 

#include<myhead.h>
int main(int argc, const char *argv[])
{
	//打开管道文件
	int rfd=-1;
	//只读形式打开
	if((rfd=open("./myfifo",O_RDONLY))==-1)
	{
		perror("open error");
		return -1;
	}
	//定义容器
	char rbuf[100]="";
	while(1)
	{
		//清空
		bzero(rbuf,sizeof(rbuf));
		//读取管道中的数据
		read(rfd,rbuf,sizeof(rbuf));
		//输出结果
		printf("receive data is:%s\n",rbuf);
		//判断结果
		if(strcmp(rbuf,"quit")==0)
		{
			break;
		}
	}
	close(rfd);
return 0;
}