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GNU Screen, commonly referred to as screen, is a program that enables the creation of multiple sessions and virtual terminals within a single terminal. Among other features, it enables the preserved state of sessions, the deattaching and reattaching of sessions, and copy and paste functionality.


USE flags

USE flags for app-misc/screen screen manager with VT100/ANSI terminal emulation

debug Enable extra debug codepaths, like asserts and extra output. If you want to get meaningful backtraces see
multiuser Enable multiuser support (by setting correct permissions)
nethack Express error messages in nethack style
pam Add support for PAM (Pluggable Authentication Modules)DANGEROUS to arbitrarily flip
selinux !!internal use only!! Security Enhanced Linux support, this must be set by the selinux profile or breakage will occur


Install app-misc/screen with the emerge command:

root #emerge --ask app-misc/screen


The configuration files are located in /etc/screenrc and ~/.screenrc.


General usage of screen.

Start session

Screen can be started with the following command:

user $screen

Once started is will create a socket for the session in /tmp/screen/S-<username> where <username> is the current user running screen.

Any key combination can be used within the session with the exception of Ctrl+a which initiates screen's Command-Mode.

Give the session a reasonable name on start up:

user $screen -t portage

Start a command in a screen session without attaching to it (similar to a daemon):

user $screen -t portage -d -m emerge -uDN @world


In Command Mode (after pressing Ctrl+a) the following key combinations can be used:


  • ? - Show quick help information.
  • d - Detach from the current session, all windows will continue to run in the background.

Creating and managing windows

  • c - create another window
  • n or Space - Switch to the next window.
  • p or Backspace - Switch to the previous window.
  • 0 - Switch to window 0 (similar for 1-9).
  • ', then a number or title - switch to window with given number or title, used to reach windows numbered above 9.
  • Ctrl+a - Switch to last used window.
  • Shift+a - Set title for window.
  • " - Display a list of windows, which can be navigated with arrow keys and selected with Enter or Space
  • w - Display a non-interactive list of windows at the bottom of screen (see Hardstatus Customization)

Copy, paste, and scroll operations

  • Esc - Begin "copy mode", which allows scrolling and copying of window contents with following keys.
    • Ctrl+B - Scroll up in copy mode.
    • Ctrl+F - Scroll down in copy mode.
    • arrow keys - Move the cursor in copy mode.
    • Space or Enter - Begin or end copying.
  • ] = Paste the text copied in copy mode.

Logging and monitoring

  • Shift+h = start/stop logging everything displayed on current window. log will be saved as a file named screenlog.X under the directory in which screen was run
  • h = (disabled in default configuration) dump the current contents of the current window to a file named hardcopy.X under the directory in which screen was run
  • Shift+m = start/stop monitoring current window for activity, any output produced by a program will cause an alert
  • _ = start/stop monitoring for inactivity (i.e. a long and output producing command finishes running)

Resume session

After the session is detached, all the active terminals remain active and so do commands that did not finish. To list existing sessions:

user $screen -ls
There is a screen on:
        30014.pts-1.disi-bigtop (Detached)
1 Socket in /tmp/screen/S-disi.

To resume the session displayed above:

user $screen -r 30014.pts-1.disi-bigtop


Initiate screen with a human readable session name:

user $screen -S multi

All other clients to view (and act on) the active live terminal can join by running:

user $screen -x multi

Then its like conference call style terminal.

Session within session recursion

A Screen may be used within a Screen session. This occurs when connecting to a another host's Screen session from within a Screen session.

To signal the secondary (remote) Screen session with the Meta key, issue the key twice to signal the second (remote) Session.

Ctrl+a Normal meta key usage on local screen
Ctrl+aa Signals the second (remote) Session
Ctrl+aaa Signals the third (remote) Session
Ctrl+aaaa Signals the fourth (remote) Session, and so on

Some tend to remap the Meta key on the other terminals so they don't have to count. However, if using the console/terminal often, there tends to be a shortage of keys on the keyboard.

Hardstatus customization

Customizing the status line, or hardstatus line in GNU Screen terminology is quite common. To get started, for example:

FILE $HOME/.screenrc
hardstatus alwayslastline
hardstatus string '%{= kG}[ %{G}%H %{g}][%= %{= kw}%?%-Lw%?%{+b m}(%{W}%n*%f%t%?(%u)%?%{m})%{-b w}%?%+Lw%?%?%= %{g}][%{c} %D %M %d %{g}%c %{g}]'

Screenshot of what my hardstatus line looks like using the above hardstatus incantation, along with nine additional terminal titles (ie. screen -t bash 7 bash --noprofile") defined within the .screenrc file. Each terminal gives me Calendar (calcurse), HTop (htop), startx (manual startx/DWM WM), Root (su), WWW (elinks), EMail (mutt) and a multitude of additional (bash) shells for working in. (This screenshot unfortunately omits color.)

user $
[ localhost2 ][ 0$ Calendar  1$ HTop  2$ startx  3$ Root  4$ bash  5-$ bash  (6*$bash) ][ Tue Nov 15  3:02 ]


After quitting a text editor the contents of the edited file remain in the screen window

Add the following line to screen preferences file:

FILE $HOME/.screenrc
altscreen on

Programs with too much output make older window contents scrolled away

It is possible to increase the scrollback buffer size with the following line in the preferences file:

FILE $HOME/.screenrc
defscrollback 10000

TTY auto-login with a GNU screen session

The following will allow the system to auto-login as a specific user, and automatically initiate a GNU Screen session on tty2. A good scenario for this: being off the network, secluded from society, and entering a password is a bit redundant. The following demonstrates using the BASH Shell.

Take heed of the obvious possible security implications this has!

MinGetty will provide autologin capability along without having to use a password:

root #emerge --ask net-dialup/mingetty

Comment-out the second TTY (ie. c2, or terminal number of choosing) and add mingetty with autologin capability.

FILE /etc/inittab
-- c2:2345:respawn:/sbin/agetty 38400 tty2 linux
++ #c2:2345:respawn:/sbin/agetty 38400 tty2 linux
++ scr2:4:respawn:/sbin/mingetty --autologin USER_NAME tty2 linux

Replace the above "USER_NAME" with desired login name!

Add a line within the boot loader's configuration file to specify loading the init #4 level. (Referencing the "scr2:4" level specified within the above inittab file.) Also, utilize the "nox" option as well. (As I can recall, the line ending with "4" specifies runlevel four in correspondence to the above inittab entry. And the nox avoids XDM starting(?) If something needs further documenting here for clarification, please do so!)

The following configuration states, use framebuffer at the specified screen size using nox and start init level 4.

FILE /boot/grub/menu.lst
title Gentoo - No X using Framebuffer - GNU Screen Console
# Default Entry
    root (hd0,1)
    kernel (hd0,1)/boot/vmlinuz quiet root=/dev/sda2 video=uvesafb:nocrtc,ywrap,mtrr:3,1280x1024-16@60 nox 4

At this point, the system can now auto login on TTY2 with the default shell. Assuming the BASH shell, GNU Screen can be started automatically by adding the "screen" command to $HOME/.bash_profile file. This file is executed automatically on first login. (Make sure to start any subsequent BASH shells using the "bash --no-profile" switch, including shells started within the $HOME/.screenrc files!)

FILE $HOME/.bash_profile
# You don't need the "if/fi" statements. I only make mention to give you the idea of using a shared $HOME/.bash_profile.
# if [ $HOSTNAME = "localhost1.local" ]; then

    # Insert any $VARIABLES you want exported to the environment before GNU Screen is executed.

    # Insert any commands you want started on initial login before screen is executed.

    # vico/case checks if we're running from only a virtual tty
    vico="$(tty | grep -oE ....$)"
    case "$vico" in
        tty2) screen -wipe; ionice -c 2 -n 0 screen -RD ;;
    # Nothing further is executed after "screen -RD" unless you use "&"

# elif [ $HOSTNAME = "localhost2.local" ]; then
# fi

With a little further scripting within $HOME/.bash_profile and a second entry within /etc/inittab, runlevel 5 may be specified for auto logging in and starting the preferred graphical desktop. (ie. XFCE4, GNOME, KDE, ...) And, while still spawning a GNU Screen session onto the desktop. But this is getting a little off topic of this GNU Screen Wiki.

Enable 256 colors

In order for GNU Screen to allow applications or the terminal to use 256 colors, two requisites must be met:

  1. The "term screen-256color" line must be specified prior to any 'screen' definitions. (ie. "screen -t Mail") The resulting side effect of specifying after 'screen' definitions, the $TERM variable will be defined as 'screen' instead of the required 'screen-256color', and applications will not be able to see the terminal supports 256 colors.
  2. Requires both the application and terminal to be compiled with 256 color support.

Paste the below code prior to any "screen" definitions:

FILE $HOME/.screenrc
# Set terminfo and termcap for nice 256 color terminal
# Allow bold colors - necessary for some reason
#attrcolor b ".I" 

# Tell screen how to set colors. AB = background, AF=foreground 
#termcapinfo xterm 'Co#256:AB=\E[48;5;%dm:AF=\E[38;5;%dm' 
terminfo rxvt-unicode 'Co#256:AB=\E[48;5;%dm:AF=\E[38;5;%dm'

# Erase background with current bg color 
#defbce "on" 

# By default, screen uses an 8-color terminal emulator. Use the
# following line to enable more colors
term screen-256color

See also

  • Byob - Text-based window manager and terminal multiplexer.
  • Recommended_tools#Terminal_multiplexers — other terminal multiplexers.
  • Tmux — a program that enables a number of terminals (or windows), each running a separate program, to be created, accessed, and controlled from a single screen or terminal window.