Linux · File Permissions & Ownership

You set umask 027 in your shell and it works, but new users on the system still get a different default. Where does the system-wide umask actually come from?

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More in File Permissions & Ownership

You own a file and want to give it away to another user by changing its owner. Why does chown fail for you?

In the first column of ls -l output you see a leading character like d, l, or c before the rwx bits. What does that character encode, and what are the main codes?

In a line like -rw-r--r-- 1 kofler kofler ..., there is a number right after the ten type-and-permission characters. What does that number mean?

Every Linux file carries an owner, a group, and permission bits. How many permission bits are there, and how are they grouped?

A user has no write bit on a file, yet they delete it anyway. How is that possible?

A file is rw-r--r-- and you want every user on the system to be able to read it too. Using symbolic chmod, what command does that?

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