Linux permissions (not SELinux)

File permissions: Linux permissions come in a numerical format; the first number represents the owner, the second number represents the group, and the third number represents all other users:

  • Permissions:
    • Owner: First number
    • Group: Second number
    • All other users: Third number
  • Numerical values:
    • 4: Read (r)
    • 2: Write (w)
    • 1: Execute (x)

Unlike a Windows permission that will execute an application, the execute function in Linux allows you to view or search.

A permission of 6 would be read and write. A value of 2 would be write, and a value of 7 would be read, write, and execute. Some examples are as follows:

  • Example 1: If I have 764 access to File A, this could be broken down as:
    • Owner: Read, write, and ...

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