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TechKnowSurge Catalog Arcade Octal Unix Permissions
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Octal Unix Permissions

Race the clock converting Unix permissions between rwx and octal.

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⚑ Complete this arcade to capture a CTF flag worth 5 points.

About this arcade

When you are fixing a file on a Linux box, nobody hands you a lookup table: ls -l shows rwxr-x---, chmod wants 750, and you need the translation without stopping to add it up. This timed round builds exactly that speed.

Each round throws a permission at you and starts the clock — a symbolic string to turn into octal, an octal value to write out as rwx, or an access requirement to turn into a chmod value. Same r = 4, w = 2, x = 1 as calm practice, now under pressure.

What you'll learn

Aligned to

CompTIA Tech+
1.1 Compare and contrast notational systems.
3.2 Compare and contrast components of an operating system.

Key terms

Octal
A base-8 number system using digits 0 through 7, where each digit represents exactly three binary bits; commonly used in Unix and Linux file permission notation because a three-bit permission group (read, write, execute) maps cleanly to a single octal digit.
Octal Notation
A base-8 numbering system used in Unix/Linux to represent file permission settings as a three-digit value, where each digit corresponds to user, group, and other access levels.
Read, Write, Execute
rwx
The three permission types in Unix/Linux: read allows viewing a file, write allows modifying it, and execute allows running it as a program or traversing a directory.
Linux File Permissions
A permission model in Linux that assigns read, write, and execute rights separately to three categories: the owning user, the owning group, and all others.
chmod
A Unix/Linux command used to change the permission settings of a file or directory using symbolic or octal values.
File Permissions
Settings on a Unix/Linux file or directory that control read, write, and execute access for the owner, group, and all other users.
Binary
The base-2 number system that uses only the digits 0 and 1; the native language of digital computers, which store and process data as electrical on/off states.
Bit
Short for binary digit, the smallest unit of data in computing, holding a single value of 0 or 1; all digital information is ultimately composed of bits.

Topics

Octal Linux File Permissions Number Systems

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