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Security · easy

2. Linux Permissions: chmod, chown, and umask

Octal permissions and ownership.

1 min read2 questionsup to 50 XPtopic 2/4

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Permissions apply to User (u), Group (g), and Others (o): - Read = 4, Write = 2, Execute = 1. - `chmod 755 script.sh` -> rwxr-xr-x. - `chown user:group file` changes user and group ownership.

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Check your understanding

1. What numeric value represents read and execute permissions (r-x) in octal notation?
5 (4 + 1)6 (4 + 2)7 (4 + 2 + 1)3 (2 + 1)
2. Which command changes the owner and group of a directory recursively?
chown -R user:group /pathchmod -R 777 /pathumask 022usermod user

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