How to use Linux Screen

Screen is a terminal multiplexer.  It means that we can start a screen session and then open any number of windows inside that session. Processes running in Screen will continue to run when their window is not visible even if  it will be disconnected.

Install Linux GNU Screen

The screen package is pre-installed on most Linux distros nowadays. You can check if it is installed on your system by typing:

screen --version

In case don’t have screen installed on system, we can easily install it by using the package manager.

Install Linux Screen depends on flavor of screen

sudo apt updatesudo apt install screen
sudo yum install screen

Starting Linux Screen

To start a screen session, simply type screen in your console:

screen

This will open a screen session and will create a new window.

Now can have opened a screen session, get a list of commands by typing:

Ctrl+a ?

screen -help

Starting Named Session

Named sessions are useful when you run multiple screen sessions. To create a named session, run the screen command with the following arguments:

screen -S session_name

It’s good practice to choose a descriptive session name.

Working with Linux Screen Windows

When you start a new screen session, it creates a single window with a shell in it.

You can have multiple windows inside a Screen session.

Below are some most common commands for managing Linux Screen Windows:

  • Ctrl+a c Create a new window (with shell).
  • Ctrl+a " List all windows.
  • Ctrl+a 0 Switch to window 0 (by number).
  • Ctrl+a A Rename the current window.
  • Ctrl+a S Split current region horizontally into two regions.
  • Ctrl+a | Split current region vertically into two regions.
  • Ctrl+a tab Switch the input focus to the next region.
  • Ctrl+a Ctrl+a Toggle between the current and previous windows
  • Ctrl+a Q Close all regions but the current one.
  • Ctrl+a X Close the current region.

Detach from Linux Screen

We can detach from the screen session at any time by typing:

Ctrl+a

Reattach a Linux Screen

To resume screen session use the following command:

screen -r

In case  have multiple screen sessions running on machine, will need to append the screen session ID after the r switch.

To find the session ID list the current running screen sessions with:

screen -ls
There are screens on:
    10838.pts-0.linuxize-desktop   (Detached)
    10348.pts-0.linuxize-desktop   (Detached)
2 Sockets in /run/screens/S-linuxize.

If you want to restore screen 10838.pts-0, then type the following command:

screen -r 10838
to detach a screen session use
sreen -r -d

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