Su (Unix)

su
Original author(s)
Developer(s)AT&T Bell Laboratories
Initial releaseNovember 3, 1971; 53 years ago (1971-11-03)
Operating systemUnix and Unix-like
TypeCommand

The Unix command su, which stands for 'substitute user'[1][2] (or historically 'superuser'[3][4]), is used by a computer user to execute commands with the privileges of another user account. When executed it invokes a shell without changing the current working directory or the user environment.

When the command is used without specifying the new user id as a command line argument, it defaults to using the superuser account (user id 0) of the system.

  1. ^ "su(1) - Linux manual page". April 2, 2021. su - run a command with substitute user and group ID
  2. ^ "Unix Programmer's Manual, Seventh Edition, Volume 1" (PDF). January 1, 1979. p. 174. Archived (PDF) from the original on Jan 20, 2022. su - substitute user id temporarily
  3. ^ "Unix Programmer's Manual" (PDF). November 3, 1971. p. 17. Archived (PDF) from the original on March 17, 2022. su -- become privileged user... su allows one to become the super-user.
  4. ^ "Unix Programmer's Manual - Table of Contents" (PDF). November 3, 1971. Archived (PDF) from the original on March 17, 2022. su: become super-user