SHELL problems encountered today

The SHELL problem encountered today-general Linux technology-Linux programming and kernel information. The following is a detailed description. In linux, how to use a script to obtain the permissions of a file is to convert the permissions in the form of-rwx -- x to 711. Remember to use chmod 711 for recovery.

At the beginning, I used ls-l to get the data, and then printed the first column with awk. I was going to use the lookup method, later, I couldn't figure out how to analyze every character in-rwx -- x in SHELL, so I gave up;

In the/usr/bin directory, locate the ls-l * acl * command: getfacl. You can get the acl of the file, contains the permissions of the owner, group, and other users on the file, but s and S cannot be obtained;

I want to write a small program in C and call the stat () function to obtain the attributes of the file so as to obtain all the permission attributes. I didn't expect man stat to find that linux itself has a stat command, I took a closer look and met my requirements.

In this way, I get what I want.