What is the screen command in Linux?

The screen command is a terminal multiplexer that allows you to create, manage, and switch between multiple terminal sessions within a single terminal window.

How do I detach from a screen session?

Press Ctrl+A followed by D to detach from a screen session. The session continues running in the background.

How do I reattach to a screen session?

Use 'screen -r' to reattach to a detached session, or 'screen -r session_name' for a specific session.

screen Command in Linux - Terminal Multiplexer

Syntax

                        screen [OPTIONS] [COMMAND [ARGS]]
                        screen -r [SESSION_NAME]
                        screen -list
                    

The screen command allows you to run multiple terminal sessions, detach from them, and reattach later, making it ideal for long-running processes and remote work.

Common Options

Option	Description
`-S name`	Create a new session with specified name
`-r [name]`	Reattach to a detached session
`-d`	Detach the session (force detach if attached elsewhere)
`-D`	Detach and logout remote session
`-list`	List all screen sessions
`-ls`	Same as -list
`-x`	Attach to session without detaching other users
`-R`	Reattach if possible, otherwise create new session
`-c file`	Use specified config file
`-m`	Force creation of new session

Basic Usage

Starting and managing sessions

                        # Start a new screen session
                        screen
                        
                        # Start a named session
                        screen -S mysession
                        
                        # Start session with a command
                        screen -S backup tar -czf backup.tar.gz /home/user/
                        
                        # List all sessions
                        screen -list
                        screen -ls
                    

Create and list screen sessions

Detaching and reattaching

                        # Detach from current session (inside screen)
                        # Press: Ctrl+A then D
                        
                        # Reattach to the last session
                        screen -r
                        
                        # Reattach to specific session
                        screen -r mysession
                        
                        # Reattach to session by PID
                        screen -r 12345
                        
                        # Force reattach (detach others first)
                        screen -d -r mysession
                    

Detach from and reattach to screen sessions

Session management

                        # Create new session or reattach if exists
                        screen -R mysession
                        
                        # Attach without detaching others (multiuser)
                        screen -x mysession
                        
                        # Kill a detached session
                        screen -S mysession -X quit
                        
                        # Send command to detached session
                        screen -S mysession -X stuff "ls -la\n"
                    

Advanced session management operations

Screen Key Bindings

Essential key combinations (Ctrl+A prefix)

Key Combination	Action
`Ctrl+A, D`	Detach from session
`Ctrl+A, C`	Create new window
`Ctrl+A, N`	Switch to next window
`Ctrl+A, P`	Switch to previous window
`Ctrl+A, 0-9`	Switch to window number
`Ctrl+A, "`	List all windows
`Ctrl+A, A`	Rename current window
`Ctrl+A, K`	Kill current window
`Ctrl+A, S`	Split screen horizontally
`Ctrl+A, \|`	Split screen vertically
`Ctrl+A, Tab`	Switch between split regions
`Ctrl+A, X`	Close current split region
`Ctrl+A, Q`	Close all split regions except current
`Ctrl+A, ?`	Show help (key bindings)

Window Management

Creating and switching windows

                        # Inside screen session:
                        # Create new window: Ctrl+A, C
                        # Switch to next window: Ctrl+A, N
                        # Switch to previous window: Ctrl+A, P
                        # Switch to window 0: Ctrl+A, 0
                        # Switch to window 1: Ctrl+A, 1
                        # List windows: Ctrl+A, "
                        
                        # From command line:
                        # Create session with multiple windows
                        screen -S multiwin
                        # Then inside screen, create more windows with Ctrl+A, C
                        
                        # Start session and immediately create named window
                        screen -S work -t editor vim
                    

Manage multiple windows within a screen session

Window naming and organization

                        # Rename current window (inside screen)
                        # Press: Ctrl+A, A
                        # Then type new name
                        
                        # Create window with specific name
                        # Press: Ctrl+A, C
                        # Then: Ctrl+A, A to rename
                        
                        # Example session setup:
                        screen -S development
                        # Window 0: editor (Ctrl+A, A, type "editor")
                        # Window 1: server (Ctrl+A, C, Ctrl+A, A, type "server")
                        # Window 2: logs (Ctrl+A, C, Ctrl+A, A, type "logs")
                    

Organize and name windows for better workflow

Screen Splitting

Horizontal and vertical splits

                        # Split screen horizontally
                        # Press: Ctrl+A, S
                        
                        # Split screen vertically (if supported)
                        # Press: Ctrl+A, |
                        
                        # Switch between split regions
                        # Press: Ctrl+A, Tab
                        
                        # Create new window in current region
                        # Press: Ctrl+A, C
                        
                        # Close current split region
                        # Press: Ctrl+A, X
                        
                        # Close all splits except current
                        # Press: Ctrl+A, Q
                    

Split screen to view multiple windows simultaneously

Practical splitting workflow

                        # Example workflow:
                        # 1. Start screen session
                        screen -S coding
                        
                        # 2. Split horizontally
                        # Ctrl+A, S
                        
                        # 3. Move to bottom region
                        # Ctrl+A, Tab
                        
                        # 4. Create new window for logs
                        # Ctrl+A, C
                        
                        # 5. Start log monitoring
                        tail -f /var/log/app.log
                        
                        # 6. Switch back to top region
                        # Ctrl+A, Tab
                        
                        # 7. Start editor
                        vim mycode.py
                    

Example workflow using screen splitting for development

Practical Examples

Long-running processes

                        # Start backup process in screen
                        screen -S backup
                        rsync -av /home/user/ user@backup-server:/backups/
                        # Detach: Ctrl+A, D
                        
                        # Check progress later
                        screen -r backup
                        
                        # Start compilation in background
                        screen -S compile -d -m make -j4
                        
                        # Monitor system updates
                        screen -S updates
                        sudo apt update && sudo apt upgrade
                        # Detach and check later
                    

Use screen for long-running processes that shouldn't be interrupted

Development environment

                        # Create development session
                        screen -S dev
                        
                        # Window 0: Editor
                        vim project.py
                        # Ctrl+A, A, rename to "editor"
                        
                        # Window 1: Server
                        # Ctrl+A, C
                        python manage.py runserver
                        # Ctrl+A, A, rename to "server"
                        
                        # Window 2: Database
                        # Ctrl+A, C
                        mysql -u user -p database
                        # Ctrl+A, A, rename to "database"
                        
                        # Window 3: Logs
                        # Ctrl+A, C
                        tail -f /var/log/app.log
                        # Ctrl+A, A, rename to "logs"
                    

Set up a complete development environment with multiple windows

Remote server management

# SSH to server and start screen ssh [email protected] screen -S admin # Window 0: System monitoring htop # Window 1: Log monitoring # Ctrl+A, C tail -f /var/log/syslog # Window 2: Service management # Ctrl+A, C sudo systemctl status nginx # Detach and logout # Ctrl+A, D exit # Later, reconnect and reattach ssh [email protected] screen -r admin

Manage remote servers with persistent screen sessions

Configuration

Screen configuration file (.screenrc)

                        # ~/.screenrc example configuration
                        
                        # Change escape key from Ctrl+A to Ctrl+J
                        escape ^Jj
                        
                        # Disable startup message
                        startup_message off
                        
                        # Set scrollback buffer
                        defscrollback 10000
                        
                        # Enable visual bell
                        vbell on
                        vbell_msg "Bell in window %"
                        
                        # Set default shell
                        shell -$SHELL
                        
                        # Window numbering starts at 1
                        bind c screen 1
                        bind 0 select 10
                        
                        # Status line
                        hardstatus alwayslastline
                        hardstatus string '%{= kG}[%{G}%H%? %1`%?%{g}][%= %{= kw}%-w%{+b yk} %n*%t%?(%u)%? %{-}%+w %=%{g}][%{B}%m/%d %{W}%C%A%{g}]'
                        
                        # Enable mouse scrolling
                        termcapinfo xterm* ti@:te@
                        
                        # Auto-detach on hangup
                        autodetach on
                    

Customize screen behavior with configuration file

Advanced configuration options

                        # ~/.screenrc advanced settings
                        
                        # Logging
                        deflog on
                        logfile /tmp/screen-%Y%m%d-%n.log
                        
                        # Activity monitoring
                        activity "Activity in window %n"
                        
                        # Silence monitoring
                        silence on
                        silencewait 15
                        
                        # Password protection
                        password ODSJQf.4IJN7E
                        
                        # Multi-user support
                        multiuser on
                        acladd john
                        aclchg john +rwx "#?"
                        
                        # Key bindings
                        bind r source ~/.screenrc
                        bind R eval "source ~/.screenrc" "echo '.screenrc reloaded'"
                        bind x remove
                        bind j focus down
                        bind k focus up
                        bind h focus left
                        bind l focus right
                    

Advanced screen configuration for power users

Troubleshooting

Common Issues and Solutions

Cannot reattach to session - Check if session exists with screen -ls
Session appears attached elsewhere - Use screen -d -r sessionname to force reattach
Screen freezes - Press Ctrl+Q to unfreeze (Ctrl+S freezes)
Cannot create new window - Check if you've reached the window limit
Lost session after network disconnect - Sessions should persist; check with screen -ls

Session recovery and cleanup

                        # List all sessions including dead ones
                        screen -ls
                        
                        # Clean up dead sessions
                        screen -wipe
                        
                        # Force kill a session
                        screen -S sessionname -X quit
                        
                        # Kill all detached sessions
                        screen -ls | grep Detached | cut -d. -f1 | awk '{print $1}' | xargs kill
                        
                        # Recover from corrupted session
                        screen -D -R sessionname
                        
                        # Check screen processes
                        ps aux | grep screen
                    

Recover and clean up screen sessions

Best Practices

Screen Usage Best Practices

Always use named sessions for better organization
Name your windows descriptively for easy identification
Regularly clean up unused sessions with screen -wipe
Use configuration file to customize key bindings and behavior
Document your screen setup for team members
Consider using tmux for more advanced features

Security Considerations

Be careful with multi-user sessions and permissions
Use password protection for sensitive sessions
Regularly audit active sessions
Avoid running privileged commands in shared sessions
Log out properly to prevent session hijacking

screen Command