my_chmod.c
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
int main(int argc, char ** argv)
{
int mode;
int mode_u;
int mode_g;
int mode_o;
char* path;
if(argc < 3) {
printf("%s <mode num> <target file>\n", argv[0]);
exit(0);
}
// 将字符串转换成整型
mode = atoi(argv[1]);
printf("%d\n", mode);
if(mode > 777 || mode < 0) {
printf("mode num error!\n");
exit(0);
}
// 传进来的数当作八进制数，转换成十进制
mode_u = mode / 100;
mode_g = (mode - (mode_u*100)) / 10;
mode_o = mode - (mode_u*100) - (mode_g*10);
mode = (mode_u * 8 * 8) + (mode_g * 8) + mode_o;
printf("The result mode we get-->%d\n", mode);
path = argv[2];
if(chmod(path, mode) == 1) {
perror("chmod error");
exit(1);
} else {
puts("Modify Success!");
}
return 0;
}
测试 查看结果
./my_chmod 776 my_chmod.c
ll
./my_chmod 777 my_chomd.c
ll
