2023.05.04 IO进程线程DAY3

1. 打印指定目录下的所有文件名，除了隐藏文件，输入编号，可以将编号对应的文件内容显示在终端上。

//代码
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 


//1.指针数组

int main(int argc, const char *argv[])
{
	DIR *dp = opendir("../day3/");   //目录流指针
	if(NULL == dp)
	{
		perror("opendir");
		return -1;
	}

	int count=1,i=0;
	struct dirent *rdp[99];
		
	while(1)
	{
		struct dirent *rp = readdir(dp);
		if(NULL == rp)
		{
			if(0 == errno)
			{
				printf("目录输出完毕\n");  //返回NULL并且不更新errno时，输出完毕
				break;
			}
			else
			{
				perror("readdir");
				return -1;
			}
		}
		if(rp->d_name[0] != '.')
		{
			printf("[%d] %s\n",count++,rp->d_name);
			rdp[i++] = rp;
		}
	}




	int n;
	printf("请输入查看文件编号:");
	scanf("%d",&n);
	int fd = open(rdp[n-1]->d_name, O_RDONLY);
	if(fd == -1)
	{
		perror("open");
		return -1;
	}
	char buf[32] = "";
	while(1)
	{
		bzero(buf,sizeof(buf));
		int res = read(fd,buf,sizeof(buf)-1);
		if(res == 0)
			break;
		printf("%s",buf);

	}
	close(fd);
	closedir(dp);

	return 0;
}

2. 显示指定路径下所有文件的权限 硬链接数 时间 以及名字

//代码
#include 
#include 
#include 
#include 
#include 
#include 
#include 

void get_FilePermission(mode_t mode)
{
	for(int i=0,t=0400;i<9;i++,t=t>>1)
	{
		if((mode&t) && i%3==0)
			putchar('r');
		else if((mode&t) && i%3==1)
			putchar('w');
		else if((mode&t) && i%3==2)
			putchar('x');
		else
			putchar('-');
	}
}

void FileInfo(const char *pathname)
{	
	struct stat buf;
	if(stat(pathname,&buf) < 0)
	{
		perror("stat");
		return;
	}
	
	//文件类型和权限
	get_FilePermission(buf.st_mode);

	//硬链接数
	printf(" %ld",buf.st_nlink);

	//用户和用户组
	printf(" %d %d",buf.st_uid,buf.st_gid);

	//文件大小
	printf(" %5ld",buf.st_size);

	//时间
	struct tm time;
	localtime_r(&buf.st_mtime,&time);
	printf(" %d.%02d.%02d %02d:%02d:%02d",time.tm_year+1900,time.tm_mon+1,time.tm_mday,time.tm_hour,time.tm_min,time.tm_sec);

	//文件名
	printf(" %s\n", pathname);
}

int main(int argc, const char *argv[])
{
	DIR *dp = opendir("../day3/");
	if(NULL == dp)
	{
		perror("opendir");
		return -1;
	}

	while(1)
	{
		struct dirent *rp = readdir(dp);
		if(NULL == rp)
		{
			if(0 == errno)
				break;
			else
				return -1;
		}
		FileInfo(rp->d_name);
	}
	closedir(dp);

	return 0;
}


//运行结果
zzy@zzy-vm:~/hqyj/IO/day3$ ./a.out 
rw-rw-r-- 1 1000 1000   694 2023.05.04 18:26:06 test1.c
rwxrwxr-x 1 1000 1000   663 2023.05.04 13:39:43 copy.txt
rw-rw-r-- 1 1000 1000  1267 2023.05.04 18:42:10 test3.c
rwxrwxr-x 7 1000 1000  4096 2023.05.04 10:10:08 ..
rw-rw-r-- 1 1000 1000  1065 2023.05.04 17:22:24 test5.c
rwxrwxr-x 2 1000 1000  4096 2023.05.04 18:42:14 .
rwxrwxr-x 1 1000 1000 17256 2023.05.04 18:42:14 a.out
rw-rw-r-- 1 1000 1000  1087 2023.05.04 18:28:17 test4.c
rw-rw-r-- 1 1000 1000  1065 2023.05.04 17:22:07 test2.c