Linux: Screen
2014-05-14
A small tool that helps you to:
1. keep a program running while you disconnect the ssh session (irssi, big copy job, compile stuff, …)
2. deal with multiple programs in one terminal
tmux is more modern and has for example a easier to read config file. But on CentOS it is for example not available by default, so I still prefer screen. For the same reason I’m using vi, but that’s another topic.
Here is my cheat sheet of the commands:
| create a screen session | |
|---|---|
| open a new session | screen |
| open a new session and give it a name | screen -S session_name |
| detach | |
| detached a session | Ctrl+a d |
| list screen sessions | screen -ls |
| rename a session (inside screen) | Ctrl+a :sessionname session_name |
| rename a session (outside screen) | screen -S old_session_name -X sessionname new_session_name |
| attach | |
| attach a session | screen -r |
| list current sessions | screen -ls |
| attach a specific session | screen -r your_screen_name |
| adjust sessions | |
| rescale application inside the session | screen -r -A |
| attach a session that is attached somewhere else (detach and attach) |
screen -r -D |
| attach to a not detached screen (“screen sharing”) |
screen -x |
| view connections to the current session | Ctrl+a * |
| windows | |
| create a new one window | Ctrl+a c |
| cycle through the windows | Ctrl+a n Ctrl+a space |
| cycle backwards | Ctrl+a p |
| show window list | Ctrl+a w |
| switch to a specific windows first window is 0, second one = 1, … |
Ctrl+a number |
| cycle between the current window and the last used window | Ctrl+a a |
| rename current window | Ctrl+a A |
| selection a window from a list | Ctrl+a “ |
| force application to fit into the current screen size | Ctrl+a F |
| movement/scrolling | |
| activate copy mode | Ctrl+a Esc Ctrl+a [ |
| move cursor | – PgUp/PgDn or Ctrl+b/Ctrl+f to scroll one page – Ctrl+u/Ctrl+d: scroll half of a page – arrow keys, j/k or +/-L scroll one line – G: moves to the bottom – ESC: to exit copy mode |
| search | |
| search forward in copy mode | /string_to_find_xyz |
| search backwards | ?string_to_find_xyz |
| copy/paste | |
| copy | – navigate to beginning – press Enter – navigate to the end – press Enter |
| insert the text | Ctrl+a ] |
| split screen | |
| horizontal split | – create a new pane – switch to the new pane – create a window inside the new pane that means: Ctrl+a S Ctrl+a Tab Ctrl+a c |
| switch between the panes | Ctrl+a Tab |
| vertical split | Ctrl+a | requires version 4.01 or newer patches for OSX |
| close a pane | Ctrl+A X |
| ending windows/sessions | |
| kill a window | Ctrl+a K |
| kill all windows and terminate the screen session | Ctrl+a \ |
| lock your session | Ctrl+x |
| daemon mode | |
| daemon for poor people… | screen -dmS a_session_name /opt/script.sh |
| start daemon as a different user | su -s /bin/bash – username -c “screen -dmS a_session_name /home/username/script.sh” |
| logs | |
| create a log | >screen -S ping_log -d -m -L ping google.de >sleep 60 >screen -r ping_log -X quit The logfile is written to the current directory and is called screenlog.? |
config file
Here is my ~/.screenrc
# in case you don't like Ctrl+a for the shortcuts you can change it
# for example you can use the ` key. It makes Ctrl+a available to jump to the first character of the command line
#escape ``
bufferfile $HOME/.screen_buffer
hardcopydir $HOME/.screen
startup_message off
vbell off
defutf8 on
defscrollback 10000
msgwait 2
term screen-256color
#enable scrolling mechanism
termcapinfo xterm* ti@:te@
#F1-F9= select window 1-9
bindkey -k k1 select 1
bindkey -k k2 select 2
bindkey -k k3 select 3
bindkey -k k4 select 4
bindkey -k k5 select 5
bindkey -k k6 select 6
bindkey -k k7 select 7
bindkey -k k8 select 8
bindkey -k k9 select 9
hardstatus on
hardstatus alwayslastline
hardstatus string '%{= K7} %{= K7}%-w%{= 70}%n %t%{= K7}%+w %-= | %{= K7}%Y-%m-%d %D %c'
#http://michael-prokop.at/computer/config/.screenrc
# %{= K7} default color = bright blac[K] background; white foreground
# %{= K7}%-w -w means before active window -> bright blac[K] background; white foreground
# %{= 70}%n %t number and text of the windows will be displayed; backgroud color 7 is white, foreground color 0 means black
# %{= Kd}%+w +w means after active window -> bright blac[K] background; white font
# %-= move the rest of the text to the right
# | print a | character
# %{= Kd}%Y-%m-%d %D %c change the color again to bright blac[K] background; white foreground; display Year-Month-Day weekday time(24h format)
#default window name
shelltitle shell
# start with window 1 instead of 0
bind c screen 1
bind ^c screen 1
bind 0 select 10
#create three windows by default and select the first one
screen -t shell 1
screen -t shell 2
screen -t shell 3
select 1