screen command

Detailed Explanation

screen is a full-screen window manager that multiplexes a physical terminal between several processes, typically interactive shells. It allows you to start a process, detach from it, and then reattach to it later, even from a different physical terminal or SSH connection. This is invaluable for running long tasks remotely.

Basic Syntax

screen [ -options ] [ cmd [ args ] ]

Common Flags/Options

Option	Description
-S <name>	Create a new session with a descriptive name.
-ls, -list	List currently running screen sessions.
-r [name]	Reattach to a detached screen session.
-d [name]	Detach a running screen session.

Common Interactive Commands (Keyboard Shortcuts)

Inside a screen session, commands start with Ctrl+A (C-a):

• C-a d: Detach from the session (leaves it running in the background).
• C-a c: Create a new window within the session.
• C-a n / C-a p: Switch to the next/previous window.
• C-a ": List all windows to select one.

Real-world Examples

Start a new screen session named "compile":

screen -S compile

List active screen sessions:

screen -ls

Reattach to a session named "compile":

screen -r compile