The screen command in Linux is a terminal multiplexer that allows you to manage multiple terminal sessions from a single window. This powerful utility provides the ability to detach and reattach terminal sessions, making it invaluable for long-running processes, remote work, and multitasking on the command line.
Overview of the screen Command
The screen command enables you to create, manage, and navigate between multiple terminal sessions within a single window. Each session runs independently, and you can detach from a session and reattach later without interrupting the running processes.
Basic Syntax
The basic syntax of the screen command is:
screen [options] [command]
Options: Various options to control the behavior of screen. Command: Optional command to run within the screen session.
Installing screen
Before using the screen command, ensure that it is installed on your system. On most Linux distributions, you can install it using the package manager.
For Red Hat-based systems (RHEL, Fedora, CentOS), use:
sudo dnf install screen
Common Use Cases
Starting a New Screen Session
To start a new screen session, simply type:
screen
This will open a new screen session, and you will be placed in a new shell.
Detaching from a Session
To detach from the current screen session without terminating it, press Ctrl-A followed by Ctrl-D. You will be returned to the original terminal, and the screen session will continue running in the background.
Reattaching to a Session
To reattach to a previously detached screen session, use the -r option:
screen -r
If you have multiple detached sessions, you can list them with:
screen -ls
Then, reattach to a specific session by its ID:
screen -r <session_id>
Naming Screen Sessions
To make it easier to manage multiple sessions, you can name them using the -S option:
screen -S mysession
You can then reattach to this session by name:
screen -r mysession
Splitting the Screen
The screen command allows you to split the terminal window into multiple regions. To split the screen horizontally, press Ctrl-A followed by S. To split it vertically, press Ctrl-A followed by |.
To switch between regions, press Ctrl-A followed by Tab.
Creating Windows
You can create multiple windows within a screen session. To create a new window, press Ctrl-A followed by C. To switch between windows, press Ctrl-A followed by the window number (e.g., 0, 1, 2, etc.).
Closing a Window
To close the current window, simply exit the shell within that window by typing exit.
Example Usage
Here are some practical examples of using the screen command:
Start a new named screen session:
screen -S mysession
Detach from the session:
Press Ctrl-A followed by D.
Reattach to the named session:
screen -r mysession
Split the screen horizontally and create a new window:
Press Ctrl-A followed by S, then Ctrl-A followed by C.
Switch between windows:
Press Ctrl-A followed by the window number.
Conclusion
The screen command is a versatile tool that enhances your command-line productivity by allowing you to manage multiple terminal sessions within a single window. Whether you need to run long-term processes, work remotely, or multitask efficiently, mastering the screen command can greatly improve your Linux experience. By learning how to create, detach, reattach, and manage screen sessions, you can take full advantage of this powerful utility.
📝 For more information about the screen command, review the screen man page!
