Homework 7.29 correlation function directory and file attributes related functions

题目：Please use directory-related functions and file attribute-related functions to implement：The function to display the attributes of all files under the specified path（Except for hidden files）,类似 ls -l 一个目录

函数代码

Extract file permission functions

void mode(mode_t a)
{
    
	char s[3]={
    'r','w','x'};
	int index=0;
	for(int i=8;i>=0;i--)
	{
    
		if(a&1<<i)
		{
    
			printf("%c",s[(i+1)%3]);
		}
		else
		{
    
			printf("-");
		}
	}
}

Extract file type function

int get_fileType(mode_t m)
{
    
	switch (m & S_IFMT) 
	{
    
	case S_IFBLK:
		printf("b");break;
	case S_IFCHR:  
		printf("c");break;
	case S_IFDIR:  
		printf("d");break;
	case S_IFIFO:  
		printf("p");break;
	case S_IFLNK:  
		printf("l");break;
	case S_IFREG:  
		printf("-");break;
	case S_IFSOCK: 
		printf("s");break;
	default:
		printf("?");break;
	}
}

Get the user name function to which the file belongs

int get_usrname(uid_t uid)
{
    
	struct passwd *pwd=getpwuid(uid);
	if(NULL==pwd)
	{
    
		printf("getpwuid failed\n");
		return -1;
	}
	printf("%s",pwd->pw_name);
	return 0;
}

The function to get the user name of the group to which the file belongs

int get_grpname(gid_t gid)
{
    
	struct group*grp = getgrgid(gid);
	if(NULL ==grp)
	{
    
		printf( "getgrgid failed\n" );
		return -1;
	}
	printf( "%s" , grp->gr_name);
	return 0;
}

Extract file last modified time

int timeset(__time_t *t)
{
    
	struct tm *info=NULL;
	info=localtime(t);
	fprintf(stdout,"%d月 %02d %02d:%02d", \
			info->tm_mon+1, info->tm_mday,\
			info->tm_hour, info->tm_min);
	fflush(stdout);
	return 0;
}

主函数代码

int main(int argc, const char *argv[])
{
    
	DIR* dp =opendir(argv[1]);
	if(NULL ==dp)
	{
    
		perror( "opendir" );
		return -1;
	}
	struct dirent *rp = NULL;
	while(1)
	{
    
		rp = readdir(dp);
		if(NULL ==rp)
		{
    
			if(0 == errno)//Error codes are not updated,The directory is read to the end
			{
    
				//printf("The directory has been read\n" );
				break;
			}
			else
			{
    
				perror( "readdir" );
				return-1;
			}
		}
		if(rp->d_name[0]=='.')
		{
    
			continue;
		}
		struct stat buf;		
		char str[100];
		strcpy(str,argv[1]);
		strcat(str,rp->d_name);
		if(stat(str,&buf)<0)
		{
    
			perror("stat");
			return -1;
		}
		//文件类型以及权限
		get_fileType(buf.st_mode);
		mode(buf.st_mode);
		printf(" ");

		//硬链接数
		printf("%ld ", buf.st_nlink);

		//文件所属用户
		get_usrname(buf.st_uid);
		printf(" ");

		//文件所属组用户
		get_grpname(buf.st_gid);
		printf(" ");

		//文件大小
		printf( "%6ld ", buf.st_size);

		//文件创建日期
		timeset(&buf.st_mtime);	
		printf(" ");
		printf("%s\n",rp->d_name);
	}
	closedir(dp);
	return 0;
}

运行结果

The function to display the attributes of all files under the specified path（Except for hidden files）

使用ls -lcommand to view the file attributes of the specified directory,Verify the correctness of the above code

源代码

https://gitee.com/Wei_JiaMin/directory-and-file-properties.git