使用有名管道实现，一个进程用于给另一个进程发消息，另一个进程收到消息后，展示到终端上，并且将消息保存到文件上一份

#include<myhead.h>
//子进程获取数据并写入
void getandwrite()
{
	//打开zy1文件
	int getfd = open("./zy1",O_RDONLY);
	if(getfd == -1)
	{
		perror("getfd error");
		return ;
	}
	//打开zy1.txt文件要是没有就创建，有就追加
	int writefd = open("./zy1.txt",O_WRONLY|O_CREAT|O_APPEND,0664);
	if(writefd ==-1)
	{
		perror("writefd error");
		return ;
	}
	while(1)
	{
		sleep(1);
		char getbuf[128] = "";//存储读取的数据
		//初始化getbuf
		bzero(getbuf,sizeof(getbuf));
		read(getfd,getbuf,sizeof(getbuf));
		if(strcmp(getbuf,"quit")==0)
		{
			break;
		}
		printf("收到消息为：%s\n",getbuf);
		//将getbuf中的数据写入zy1.txt文件
		write(writefd,getbuf,strlen(getbuf));
		write(writefd,"\n",1);
	}
	close(getfd);
    exit(EXIT_SUCCESS);
}
//父进程发送数据
void set()
{
	int setfd = open("./zy1",O_WRONLY);
	if(setfd == -1)
	{
		perror("setfd error");
		return ;
	}

	while(1)
	{
		sleep(1);
		printf("请输入>>>>");
		char setbuf[128] = "";//存储输入的数据
		//初始化setbuf
		bzero(setbuf,sizeof(setbuf));
		fgets(setbuf,sizeof(setbuf),stdin);
		//去除换行符
		setbuf[strlen(setbuf)-1] = 0;
		//将setbuf中的数据写入zy1文件
		write(setfd,setbuf,strlen(setbuf));
		if(strcmp(setbuf,"quit")==0)
		{
			break;
		}

	}
	close(setfd);



}
/*********************主程序********************/
int main(int argc, char const *argv[])
{   
    if (mkfifo("./zy1",0644) == -1)
    {
        perror("mkfifo error");
        return -1;
    }
    pid_t pid = fork();
    
    if(pid ==0)
    {
		getandwrite();//子进程获取数据并写入
        printf("子进程\n");
    }
    else if(pid >0)
    {
		set();//父进程发送数据
        printf("父进程\n");
    }
    else
    {
        printf("fork error\n");
    }
	getchar();

    system("rm ./zy1");//删除生成的管道文件
    return 0;
}

使用有名管道实现两个进程间相互通信

cerate.c

#include<myhead.h>

int main(int argc, const char *argv[])
{
     if (mkfifo("./1",0664) ==-1)
    {
        perror("mkfifo error");
        return -1;
    }
    if (mkfifo("./2",0664) ==-1)
    {
        perror("mkfifo error");
        return -1;
    }

    getchar();

    system("rm ./1");
    system("rm ./2");
    return 0;
}

1.c

#include <myhead.h>

void set() //发送给2的进程函数
{

    int fd = open("./1", O_WRONLY);
    if (fd == -1)
    {
        perror("open error");
        return;
    }

    char buf[128] = "";
    while (1)
    {
        bzero(buf, sizeof(buf));

        fgets(buf, sizeof(buf), stdin);
        printf("上面你要发给2的信息：\n");
        buf[strlen(buf) - 1] = 0;
        write(fd, buf, strlen(buf));
        if (strcmp(buf, "quit") == 0)
        {
            break;
        }
        
    }
    close(fd);
}

void get() //接收2的进程函数
{
    int fd = open("./2", O_RDONLY);
    if (fd == -1)
    {
        perror("open error");
        return;
    }
    char buf[128] = "";
    while (1)
    {
        bzero(buf, sizeof(buf));
        read(fd, buf, sizeof(buf));

        if (strcmp(buf, "quit") == 0)
        {
            break;
        }
        printf("从2接收到的信息：%s\n", buf);
    }
    close(fd);
}
int main(int argc, char const *argv[])
{
    pid_t pid = fork();

    if (pid > 0)
    {
        set();
    }
    else if (pid == 0)
    {
        get();
        exit(EXIT_SUCCESS);
    }
    else
    {
        printf("error\n");
        return -1;
    }

    wait(NULL);

    return 0;
}

2.c

#include <myhead.h>
void set() //发送给1的进程函数
{

    int fd = open("./2", O_WRONLY);
    if (fd == -1)
    {
        perror("open error");
        return;
    }

    char buf[128] = "";
    while (1)
    {
        bzero(buf, sizeof(buf));
        fgets(buf, sizeof(buf), stdin);
        printf("上面你要发给1的信息：\n");
        buf[strlen(buf) - 1] = 0;
        write(fd, buf, strlen(buf));
        if (strcmp(buf, "quit") == 0)
        {
            break;
        }
        
    }
    close(fd);
}

void get() //接收1的进程函数
{
    int fd = open("./1", O_RDONLY);
    if (fd == -1)
    {
        perror("open error");
        return;
    }
    char buf[128] = "";
    while (1)
    {
        bzero(buf, sizeof(buf));
        read(fd, buf, sizeof(buf));

        if (strcmp(buf, "quit") == 0)
        {
            break;
        }
        printf("从1接收到的信息：%s\n", buf);
    }
    close(fd);
}
int main(int argc, char const *argv[])
{

    pid_t pid = fork();

    if (pid > 0)
    {
        set();
    }
    else if (pid == 0)
    {
        get();
        exit(EXIT_SUCCESS);
    }
    else
    {
        printf("error\n");
        return -1;
    }
    wait(NULL);

    return 0;
}