Understanding the Stat Command

The stat command is a powerful utility in Unix-like operating systems used to display detailed information about files and file systems. It provides a comprehensive overview of a file's metadata, including its size, modification times, access times, inode number, and permissions. This makes it an invaluable tool for system administrators, developers, and anyone who needs to inspect file attributes closely.

Displaying Numerical File Permissions

One of the most common uses of the stat command is to retrieve file permissions in a numerical format. This is particularly useful for scripting or for quickly understanding the exact permission settings of a file. The -c or --format option allows you to specify the output format. For example, to display the octal representation of file permissions followed by the filename, you can use the following command:

stat -c '%a %n' *

In this command, %a represents the file's access rights in octal format, and %n represents the filename. The asterisk (*) is a wildcard that applies the command to all files and directories in the current directory.

Retrieving Octal Permissions for Specific Directories

You can also use stat to get specific information, such as just the octal permissions, for a particular directory. This is often used in automated checks or tests where only the permission bits are relevant. The following command demonstrates how to display only the octal permissions for the /boot directory:

stat --format='%a' /boot

This command isolates the permission information, making it easy to parse and use in other scripts or applications. Understanding these commands is crucial for managing file security and integrity on Linux systems.

Further Resources

• Linux stat man page
• GNU Coreutils stat documentation
• Stack Overflow: Get file permissions in octal format using stat