stat命令的实现mystat

1.使用stat截图

2.man -k grep -r的使用

3.伪代码
首先判断输入中是否包含文件参数，如果有则继续，没有则提示用户输入错误。
然后查找并将文件的相关参数进行保存，声明结构体，并调用stat()函数给结构体赋值，将文件的设备编号、节点、文件的类型和存取的权限、连到该文件的硬链接数目等按顺序输出。

4.代码

include <sys/types.h>

include <sys/stat.h>

include <time.h>

include <stdio.h>

include <stdlib.h>

int main(int argc, char *argv[])
{
struct stat a;
if (argc != 2) {
fprintf(stderr, "Usage: %s \n", argv[0]);
exit(EXIT_FAILURE);
}
if (stat(argv[1], &a) == -1) {
perror("stat");
exit(EXIT_FAILURE);
}
printf("文件: %s\n",argv[1]);
printf("Inode: %ld\n", (long) a.st_ino);
printf("硬链接: %ld\n", (long) a.st_nlink);
printf("权限: Uid = %ld Gid = %ld\n",(long) a.st_uid, (long) a.st_gid);
printf("IO块: %ld ",(long) a.st_blksize);
switch (a.st_mode & S_IFMT)
{
case S_IFBLK: printf("块设备\n");
break;
case S_IFCHR: printf("character device\n");
break;
case S_IFDIR: printf("目录\n");
break;
case S_IFIFO: printf("FIFO/管道\n");
break;
case S_IFLNK: printf("符号链接\n");
break;
case S_IFREG: printf("普通文件\n");
break;
case S_IFSOCK: printf("socket\n");
break;
default: printf("未知?\n");
break;
}
printf("大小: %lld bytes\n",(long long) a.st_size);
printf("块: %lld\n",(long long) a.st_blocks);
printf("最近访问: %s", ctime(&a.st_atime));
printf("最近更改: %s", ctime(&a.st_mtime));
printf("最近改动: %s", ctime(&a.st_ctime));
exit(EXIT_SUCCESS);
}

5.测试代码，mystat 与stat（1）对比，提交截图