2022嵌入式8-4

• 进程间通信
• • main.c
  • 结果展示
• 进程间实时通信
• • 进程A main.c
  • 进程B main.c
  • 结果展示
• 信号捕获
• • main.c
  • 结果展示

#include
#include
#include
#include

int main(int argc, const char *argv[])
{
	//创建一个管道
	int pfd1[2] = {0};
	if(pipe(pfd1) < 0)
	{
		perror("pipe1");
		return -1;
	}
	printf("pipe1 create successn ");

	int pfd2[2] = {0};
	if(pipe(pfd2) < 0)
	{
		perror("pipe2");
		return -1;
	}
	printf("pipe2 create successn ");

	pid_t pid = fork();
	if(pid > 0)
	{
		//关闭pfd1管道的读端和pfd2管道的写端，因为父进程没用到
		close(pfd1[0]);
		close(pfd2[1]);
		char str[128] = "";
		ssize_t res;
		while(1)
		{
			bzero(str, sizeof(str));
			printf("parent input：");
			fgets(str, sizeof(str), stdin);
			str[strlen(str)-1] = '';
			if(write(pfd1[1], str, sizeof(str)) < 0)
			{
				perror("write");
				exit(0);
			}
			if(strcasecmp(str, "quit") == 0)
				break;
			bzero(str, sizeof(str));
			res = read(pfd2[0], str, sizeof(str));
			if(res < 0)
			{
				perror("read");
				return -1;
			}
			else if(0 == res)
			{
				printf("写端关闭n");
				break;
			}
			printf("父进程收到子进程说：%sn", str)
			if(strcasecmp(str, "quit") == 0)
				break;
		}
	}

	//阻塞等待子进程退出
	wait(NULL);
	close(pfd1[1]);
	close(pfd2[0]);
	else if(0 == pid)
	{
		close(pfd1[1]);
		cloose(pfd2[0]);
		//子进程从管道中读取数据
		char buf[128] = "";
		ssize_t res = 0;
		while(1)
		{
			bzero(buf, sizeof(buf));
			res = read(pfd1[0], buf, sizeof(buf));
			if(res < 0)
			{
				perror("read");
				return -1;
			}
			else if(0 == res)
			{
				printf("写端关闭n");
				break;
			}
			printf("子进程收到父进程说%sn", buf);
			if(stricasecmp(buf, "quit") == 0)
				break;
			else
				printf("child = %sn", buf);

			bzero(buf, sizeof(buf));
			printf("chile input：");
			fgets(buf, sizeof(buf), stdin);
			buf[strlen(buf)-1] = 0;
			if(write(pfd2[1], buf, sizeof(buf)) < 0)
			{
				perror("write");
				return -1;
			}
			if(stricasecmp(buf, "quit") == 0)
				break;

		}
	}
	else
	{
		perror("fork");
		return -1;
	}

	return 0;
}

#include
#include
#include
#include
#include
#include
#include
#include
#include

char buf[128] = "";
void *callBack_read(void *arg)
{
	ssize_t res;

	//以只读的方式打开有名管道文件1
	int fd_r = open("./myfifo1", O_RDONLY);
	if(fd_r < 0)
	{
		perror("open");
		return NULL;
	}
	printf("open readnoly successn");
	while(1)
	{
		bzero(buf, sizeof(buf));
		res = read(fd_r, buf, sizeof(buf));
		if(res < 0)
		{
			perror("read");
			return NULL;
		}
		else if(res == 0)
		{
			printf("对方进程退出n");
			break;
		}
		printf("read success，%sn", buf);
		if(strcasecmp(buf, "quit") == 0)
		{
			printf("已退出n");
			exit(0);
		}
	}
	pthread_exit(NULL);
	close(fd_r);
}

void *callBack_write(void *arg)
{
	//以只写的方式打开有名管道文件2
	int fd_w = open("./myfifo2", O_WRONLY);
	if(fd_w < 0)
	{
		perror("open");
		return NULL;
	}
	printf("open writenoly successn");
	while(1)
	{
		bzero(buf, sizeof(buf));
		//printf("请输入>>>");
		fgets(buf, sizeof(buf), stdin);
		buf[strlen(buf)-1] = '';

		if(write(fd_w, buf, sizeof(buf)) < 0)
		{
			perror("write");
			return NULL;
		}	
		if(strcasecmp(buf, "quit") == 0)
		{
			printf("已退出n");
			exit(0);
		}
	}
	pthread_exit(NULL);
	close(fd_w);
}
int main(int argc, const char *argv[])
{
	
	//创建两个有名管道
	umask(0);
	if(mkfifo("./myfifo1", 0777) < 0);
	{
		if(errno != 17)
		{
			perror("mkfifo");
			return -1;
		}
	}
	if(mkfifo("./myfifo2", 0777) < 0);
	{
		if(errno != 17)
		{
			perror("mkfifo");
			return -1;
		}
	}
	
	printf("mkfifo successn");

	//创建两个线程
	pthread_t tid1, tid2;
	pthread_create(&tid1, NULL, callBack_read, NULL);
	pthread_create(&tid2, NULL, callBack_write, NULL);

	pthread_join(tid1, NULL);
	pthread_join(tid2, NULL);

	return 0;
}

#include
#include
#include
#include
#include
#include
#include
#include
#include

char buf[128] = "";
void *callBack_read(void *arg)
{
	ssize_t res;

	//以只读的方式打开有名管道文件2
	int fd_r = open("./myfifo2", O_RDONLY);
	if(fd_r < 0)
	{
		perror("open");
		return NULL;
	}
	printf("open readnoly successn");
	while(1)
	{
		bzero(buf, sizeof(buf));
		res = read(fd_r, buf, sizeof(buf));
		if(res < 0)
		{
			perror("read");
			return NULL;
		}
		else if(res == 0)
		{
			printf("对方进程退出n");
			break;
		}

		printf("read success，%sn", buf);
		if(strcasecmp(buf, "quit") == 0)
		{
			printf("已退出n");
			exit(0);
		}
	}
	pthread_exit(NULL);
	close(fd_r);
}

void *callBack_write(void *arg)
{
	//以只写的方式打开有名管道文件1
	int fd_w = open("./myfifo1", O_WRONLY);
	if(fd_w < 0)
	{
		perror("open");
		return NULL;
	}
	printf("open writenoly successn");
	while(1)
	{
		bzero(buf, sizeof(buf));
	//	printf("请输入>>>");
		fgets(buf, sizeof(buf), stdin);
		buf[strlen(buf)-1] = '';
		if(write(fd_w, buf, sizeof(buf)) < 0)
		{
			perror("write");
			return NULL;
		}
		if(strcasecmp(buf, "quit") == 0)
		{
			printf("已退出n");
			exit(0);
		}
	}
	pthread_exit(NULL);
	close(fd_w);
}
int main(int argc, const char *argv[])
{
	
	//创建两个线程两个个有名管道
	umask(0);
	if(mkfifo("./myfifo1", 0777) < 0);
	{
		if(errno != 17)
		{
			perror("mkfifo");
			return -1;
		}
	}
	if(mkfifo("./myfifo2", 0777) < 0);
	{
		if(errno != 17)
		{
			perror("mkfifo");
			return -1;
		}
	}
	
	printf("mkfifo successn");

	//创建两个线程
	pthread_t tid1, tid2;
	pthread_create(&tid1, NULL, callBack_read, NULL);
	pthread_create(&tid2, NULL, callBack_write, NULL);

	pthread_join(tid1, NULL);
	pthread_join(tid2, NULL);

	return 0;
}

#include
#include 
#include 

typedef void (*sighandler_t)(int);

void handler(int sig)
{
	printf("this is handler %dn", sig);
}

int main(int argc, const char *argv[])
{
	sighandler_t s;
	s = signal(2, handler);
	if(SIG_ERR == s)
	{
		perror("signal");
		return -1;
	}

	s = signal(3, handler);
	if(SIG_ERR == s)
	{
		perror("signal");
		return -1;
	}

	s = signal(20, handler);
	if(SIG_ERR == s)
	{
		perror("signal");
		return -1;
	}
	while(1)
	{
		printf("this is mainn");
		sleep(1);
	}

	return 0;
}