Learn how to make these file lock
Why can't I put a password on a folder?
Avoid Race Conditions. For example a deadlock would occur if process 1 locks resources A and waits. To create a file or set a file timestamp usually the command touch is used. It's amazing how far Linux has come without providing for proper file locking that. How to Password Protect PDF Documents groovyPost. How can I download a protected PDF file?