Wednesday, August 6, 2014

screen

SCREEN 

Keep all your ssh processes running despite dropped connections.

Getting in

start a new screen session with session namescreen -S <name>
list running sessions/screensscreen -ls
attach to a running sessionscreen -x
… to session with namescreen -r <name>
the “ultimate attach”screen -dRR (Attaches to a screen session. If the session is attached elsewhere, detaches that other display. If no session exists, creates one. If multiple sessions exist, uses the first one.)
detach a running sessionscreen -d <name>

Escape key

All screen commands are prefixed by an escape key, by default C-a (that's Control-a, sometimes written ^a). To send a literal C-a to the programs in screen, use C-a a. This is useful when when working with screen within screen. For example C-a a n will move screen to a new window on the screen within screen.

Getting out

detachC-a d
detach and logout (quick exit)C-a D D
exit screen“C-a : quit” or exit all of the programs in screen.
force-exit screenC-a C-\ (not recommended)

Help

See helpC-a ? (lists keybindings)
The man page is the complete reference, but it's very long.

Window Management

create new windowC-a c
change to last-visited active windowC-a C-a (commonly used to flip-flop between two windows)
change to window by numberC-a <number> (only for windows 0 to 9)
change to window by number or nameC-a ' <number or title>
change to next window in listC-a n or C-a <space>
change to previous window in listC-a p or C-a <backspace>
see window listC-a " (allows you to select a window to change to)
show window barC-a w (if you don't have window bar)
close current windowClose all applications in the current window (including shell)
kill current windowC-a k (not recommended)
kill all windowsC-a \ (not recommended)
rename current windowC-a A

Split screen

split display horizontallyC-a S
split display verticallyC-a | or C-a V (for the vanilla vertical screen patch)
jump to next display regionC-a tab
remove current regionC-a X
remove all regions but the current oneC-a Q

Scripting

send a command to a named sessionscreen -S <name> -X <command>
create a new window and run ping example.comscreen -S <name> -X screen ping example.com
stuff characters into the input buffer
using bash to expand a newline character
(from here)
screen -S <name> [-p <page>] -X stuff $'quit\r'
a full example
# run bash within screen
screen -AmdS bash_shell bash
# run top within that bash session
screen -S bash_shell -p 0 -X stuff $'top\r'
 
# ... some time later
 
# stuff 'q' to tell top to quit
screen -S bash_shell -X stuff 'q'
# stuff 'exit\n' to exit bash session
screen -S bash_shell -X stuff $'exit\r'

Misc

redraw windowC-a C-l
enter copy modeC-a [ or C-a <esc> (also used for viewing scrollback buffer)
pasteC-a ]
monitor window for activityC-a M
monitor window for silenceC-a _
enter digraph (for producing non-ASCII characters)C-a C-v
lock (password protect) displayC-a x
enter screen commandC-a :
enable logging in the screen sessionC-a H