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Systems & Data Center · Foundational

chmod

The Linux command that changes file and directory permission bits using symbolic or octal notation.

Definition

Symbolic mode uses u, g, o, a with +, - or = (for example g+w). Octal mode sets all bits at once. -R applies changes recursively. Only the owner or root can change a file's mode.

Example

chmod u+x deploy.sh makes a script executable by its owner.

Exam tip

chmod -R 777 is never the right answer for fixing access problems on an exam.

Don't confuse it with

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