又要考试了

一、实现无名管道练习：父进程写入管道，子进程读取管道数据。

#include<myhead.h>
int main(int argc, const char *argv[])
{
	int fd[2];
	char buff[1024]="王吕阳，崔庆权别卷了";
	char s[1024];
	if(pipe(fd)==-1)
	{
		perror("pipe");
		return -1;
	}
	pid_t pid = fork();
	if(pid==0)
	{
		close(fd[1]);//关闭写端
		while(1)
		{
			sleep(1);
			read(fd[0],s,sizeof(s));
			printf("展旗善意提醒:%s\n",s);
		}
		close(fd[0]);//关闭读端
	}else if(pid>0)
	{
		close(fd[0]);//关闭读端
		while(1)
		{
			sleep(1);
			write(fd[1],buff,sizeof(buff));
		}
		close(fd[1]);
	}else
	{
		perror("fork");
		return -1;
	}
	return 0;
}

二、有名管道练习实现一遍练习：创建2个子父进程，父进程写入管道1，子进程读取管道2，父进程写入管道2，子进程读取管道1，实现全双工通信。

#include<myhead.h>
int main(int argc, const char *argv[])
{
	int fd1 = open("./a",O_WRONLY);
	int fd2 = open("./b",O_RDONLY);
	char arr[1024];
	char brr[1024];
	if(fd1==-1||fd2==-1)
	{
		perror("open");
		return -1;
	}
	pid_t pid = fork();
	if(pid>0)
	{
		while(1)
		{
			printf("请输入内容:");
			int res = read(0,arr,sizeof(arr));
			write(fd1,arr,res);
		}
		close(fd1);

	}else if(pid==0)
	{
		while(1)
		{
			int ress = read(fd2,brr,sizeof(brr));
			if(ress==0)
			{
				printf("退出\n");
				break;
			}
			write(1,brr,ress);
		}
		close(fd2);
	}else
	{
		perror("fork");
		return -1;
	}
	return 0;
}

#include<myhead.h>
int main(int argc, const char *argv[])
{
	int fd1 = open("./a",O_RDONLY);
	int fd2 = open("./b",O_WRONLY);
	char arr[1024];
	char brr[1024];
	if(fd1==-1||fd2==-1)
	{
		perror("open");
		return -1;
	}
	pid_t pid = fork();
	if(pid>0)
	{
		while(1)
		{
			printf("请输入内容:");
			int ress = read(0,brr,sizeof(brr));
			write(fd2,brr,ress);
		}
		close(fd2);

	}else if(pid==0)
	{
		while(1)
		{
			int res = read(fd1,arr,sizeof(arr));
			if(res==0)
			{
				printf("退出\n");
				break;
			}
			write(1,arr,res);
		}
		close(fd1);
	}else
	{
		perror("fork");
		return -1;
	}
	return 0;
}

三、进程间通信信号的默认，忽略，捕获实现一遍。

#include<myhead.h>
void a(int b)
{
	if(b==SIGTSTP)
	{
		printf("A\n");
	}
}
int main(int argc, const char *argv[])
{
/*	if(signal(SIGINT,SIG_IGN)==SIG_ERR)
	{
		perror("signal");
		return -1;
	}

	if(signal(SIGINT,SIG_DFL)==SIG_ERR)
	{
		perror("signal");
		return -1;
	}
	*/
	if(signal(SIGTSTP,a)==SIG_ERR)
	{
		perror("signal");
		return -1;
	}
	int k=0;
	while(1)
	{
		sleep(1);
		printf("按k=%d\n",k);
		k++;
	}
	return 0;
}

四、思维导图