chmod Tutorial

This is a tutorial that teaches the UNIX ®/Linux ® chmod command. It presumes that you already know how to use the ls command to list the contents of a directory.

What is chmod?

chmod is a Unix command that lets you tell the system how much (or little) access it should permit to a file.

Here are all the topics:

• Changing File Permissions
• Your Permissions
• Group Permissions
• Others’ Permissions
• The chmod command
• chmod Examples
• chmod Shortcuts
• Copying Permissions
• A Problem Solved
• A New Problem
• Setting User ID
• Quick Reference Summary
• chmod by the Numbers

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