Directly attach a remote screen session (saves a useless parent bash process)
If you enable multiuser, then you can permit others to share your screen session. The following conditions apply: 1. screen must be suid root; 2. "multiuser on" must be configured in ~/.screenrc; 3. control the others user(s) access with "aclchg": # ----- from ~/.screenrc-users ----- aclchg someuser +rx "#?" #enable r/o access to "someuser" aclchg someuser -x "#,at,aclchg,acladd,acldel,quit" # don't allow these aclchg otheruser +rwx "#?" # enable r/w access to "otheruser" aclchg otheruser -x "#,at,aclchg,acladd,acldel,quit" # don't allow them to use these commands # ----- After doing this (once), you start your session with: $ screen Then, the other user can join your terminal session(s) with youruserid: $ screen -r youruserid/ Note: the trailing "/" is required. Multiple users can share the same screen simultaneously, each with independent access controlled precisely with "aclchg" in the ~/.screenrc file. I use the following setup: # ~/.screenrc-base # default screenrc on any host source $HOME/.screenrc-base source $HOME/.screenrc-$HOST source $HOME/.screenrc-users # ----- Then, the base configurations are in ~/.screenrc-base; the host-specific configurations are in ~/.screenrc-$HOST, and the user configurations are in ~/.screenrc-users. The host-specific .screenrc file might contain some host-specific screen commands; e.g.: # ~/.screen-myhost # ----- screen -t 'anywhere' /bin/tcsh screen -t 'anywhere1' /bin/tcsh # ---- The .screenrc-base contains: # ~/.screenrc-base ## I find typing ^a (Control-a) awkward. So I set the escape key to CTRL-j instead of a. escape ^Jj termcapinfo xterm* ti@:te@: autodetach on zombie kr verbose on multiuser on
Displays a list of all the basic keyboard shortcuts in screen. Show Sample Output
Start screen in detached mode, i.e., already running on background. The command is optional, but what is the purpose on start a blank screen process that way? It's useful when invoking from a script (I manage to run many wget downloads in parallel, for example).
By default, screen tries to restore its old window sizes when attaching to resizable terminals. This command is the command-line equivalent to typing ^A F to fit an open screen session to the window.
From screen's manpage: "Attach here and now. In detail this means: If a session is running, then reattach. If necessary detach and logout remotely first. If it was not running create it and notify the user. This is the author's favorite." Toss this in your ~/.bash_profile so that you never have that "oh crap" moment where you wanted to run something in screen and didn't.
Only useful for really flakey connections (but im stuck with one for now). Though if youre in this situation ive found this to be a good way to run autossh and it does a pretty good job of detecting when the session is down and restarting. Combined with the -t and screen commands this pops you back into your working session lickety split w/ as few headaches as possible. And if autossh is a bit slow at detecting the downed ssh connection, just run this in another tab/terminal window to notify autossh that it should drop it and start over. Basically for when polling is too slow. kill -SIGUSR1 `pgrep autossh` Show Sample Output
Use GNU/screen as a terminal emulator for anything serial console related. screen /dev/tty eg. screen /dev/ttyS0 9600 MacOSX: http://www.macosxhints.com/article.php?story=20061109133825654 Cheat Sheet: http://www.catonmat.net/blog/screen-terminal-emulator-cheat-sheet/ Show Sample Output
i spent way too many hours trying to fiddle with /etc/X11/xorg.conf trying to hook up various external projectors. too bad i didn't know this would solve all my problems.
Use as: $ s host1 Will ssh to remote host upon first invocation. Then use C-a d to detatch. Running "s host1" again will resume the shell session on the remote host. Only useful in LAN environment. You'd want to start the screen on the remote host over a WAN. Adapted from Hack 34 in Linux Server Hacks 2nd Addition.
Add this to your $HOME/.bashrc file. It will only set this prompt if it is running inside screen ($WINDOW var is set)
Looks like this...
ion@atomos:~[2]$
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When you start screen as `ssh-agent screen`, agent will die after detatch. If you don't want to take care about files when stored agent's pid/socket/etc, you have to use this command.
Configures screen to always display the clock in the last line (has to be configured only once). After that you not only have got the possibility to detach sessions and run them in background, but also have got a nice clock permanently on your screen.
this bash command sets it so that when you type "screen ", it searches your running screens, and present valid auto-complete choices. The output is . Note: You must have programmable completion enabled. Check with "shopt progcomp", set with "shopt -s progcomp" Show Sample Output
Bash alias for easy irssi within screen, attempts to attach to existing irssi session, if one exists, otherwise creates one - Including wipe for when system reboots and leaves "dead" session.
Normally, if you su to another user from root and try to resume that other user's screen session, you will get an error like "Cannot open your terminal '/dev/pts/0' - please check." This is because the other user doesn't have permission for root's pty. You can get around this by running a "script" session as the new user, before trying to resume the screen session. Note you will have to execute each of the three commands separately, not all on the same line as shown here. Credit: I found this at http://www.hjackson.org/blog/archives/2008/11/29/cannot-open-your-terminal-dev-pts-please-check.
A wrapper around ssh to automatically provide logging and session handling.
This function runs ssh, which runs screen, which runs script.
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The logs and the screen session are stored on the server.
This means you can leave a session running and re-attach to it later, or from another machine.
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Requirements:
* Log sessions on a remote server
* Transparent - nothing extra to type
* No installation - nothing to copy to the server beforehand
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Features:
* Function wrapper delegating to ssh
- so nothing to remember
- uses .ssh/config as expected
- passes your command line option to ssh
* Self-contained: no scripts to install on the server
* Uses screen(1), so is:
- detachable
- re-attachable
- shareable
* Records session using script(1)
* Configurable log file location, which may contain variables or whitespace
L="$HOME" # local variable
L="\$HOME" # server variable
L="some space"
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Limitations:
* Log dir/file may not contain '~' (which would require eval on the server)
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The sessions are named by the local user connecting to the server.
Therefore if you detach and re-run the same command you will reconnect to your original session.
If you want to connect/share another's session simply run:
USER=bob ssh root@server
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The command above is stripped down to an absolute minimum.
A fully expanded and annotated version is available as a Gist (git pastebin):
https://gist.github.com/flatcap/3c42326abeb1197ee714
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If you want to add timing info to script, change the command to:
ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script --timing=\"$L-timing\" -f \"$L\"";}
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There was another line that was dependent on having un-named screen sessions. This just wouldn't do. This one works no matter what the name is. A possible improvement would be removing the perl dependence, but that doesn't effect me.
Errors in output don't matter. Stop recording: ctrl-c. Result playable with Flash too. IMPORTANT: Find a Pulse Audio device to capture from: pactl list | grep -A2 'Source #' | grep 'Name: ' | cut -d" " -f2 Show Sample Output
This command attempts to attach to existing irssi session, if one exists, otherwise creates one. I use "irc" because I use different irc clients depending on what system I am working on. Consistency is queen.
I'm not sure what apt this is, but it seems to work on most X screens, an is useful for saving power, and not straining your eyes Show Sample Output
Grabs the cmdline used to execute the process, and the environment that the process is being run under. This is much different than the 'env' command, which only lists the environment for the shell. This is very useful (to me at least) to debug various processes on my server. For example, this lets me see the environment that my apache, mysqld, bind, and other server processes have.
Here's a function I use:
aa_ps_all () { ( cd /proc && command ps -A -opid= | xargs -I'{}' sh -c 'test $PPID -ne {}&&test -r {}/cmdline&&echo -e "\n[{}]"&&tr -s "\000" " "<{}/cmdline&&echo&&tr -s "\000\033" "\nE"<{}/environ|sort&&cat {}/limits' ); }
From my .bash_profile at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html
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Use the command to create a script and bind it to a key using keyboard shortcut. eg: Script locks the screen in a loop until the command is executed again.At first it
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