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Force the user you want to watch doing things into doing his things in a screen session. Then simply attach yourself to that session with the command shown above.
Works only if you are on the same machine, of course
This command starts screen with 'htop', 'nethogs' and 'iotop' in split-screen. You have to have these three commands (of course) and specify the interface for nethogs - mine is wlan0, I could have acquired the interface from the default route extending the command but this way is simpler.
htop is a wonderful top replacement with many interactive commands and configuration options. nethogs is a program which tells which processes are using the most bandwidth. iotop tells which processes are using the most I/O.
The command creates a temporary "screenrc" file which it uses for doing the triple-monitoring. You can see several examples of screenrc files here: http://www.softpanorama.org/Utilities/Screen/screenrc_examples.shtml
If you know the benefits of screen, then this might come in handy for you. Instead of ssh'ing into a machine and then running a screen command, this can all be done on one line instead. Just have the person on the machine your ssh'ing into run something like
screen -S debug
Then you would run
ssh -t [email protected] screen -x debug
and be attached to the same screen session.
This will launch and irssi session on your server. If it's not running, it will create the session. If it's running it'll connect to it and destroy any other connections. If compositing is available, the rxvt window will have transparency added. This window will also open maximized. Anything else this does should be easily figured out in the man pages.
Directly attach a remote screen session (saves a useless parent bash process)
This command will let you just type c-a b (which means press 'ctrl' then 'a' then 'b'), and screen will save your copy buffer to /tmp/screen-exchange, and then execute xsel to copy the contents of that file into the system's X clipboard.
1. Install Conrad Parker's xsel from http://www.vergenet.net/~conrad/software/xsel/
2. Add these lines to your .screenrc
# Add cool line to make copying to x clipboard possible.
# This binds C-a b to copy screen's copy buffer to the system clipboard.
bind b eval writebuf 'exec /bin/sh -c "xsel -i -b < /tmp/screen-exchange"' 'exec /bin/sh -c "killall xsel"'
3. Restart screen.
4. Test it by typing c-a [ to enter copy mode.
5. Select some text using vi movement keys (h, j, k, l, etc...) and starting your selection by hitting the space bar, moving with vi movement keys, and then ending your selection with the space bar.
6. Type C-a b, and screen will use xsel to copy your screen copy buffer to the system's X clipboard buffer.
7. Then you can paste the screen copy buffer into any X program.
Note: If you're using Mac OSX, you can use pbcopy instead of xsel.
Also Note: The second exec in the .screenrc file, which runs killall on xsel, is necessary, because even when you redirect a file to xsel, xsel waits for you to press ctrl-c to kill it, and have it stop waiting for more input. Since xsel forces screen to wait, and I don't want to press ctrl-c, I send the equivalent of ctrl-c with killall causing xsel to write /tmp/screen-exchange to the X clipboard, and then exit. It's a hack, but it works. If you know how to get this to work without a lame hack leave a comment explaining how.
Ater person A starts his screen-session with `screen`, person B can attach to the srceen of person A with `screen -x`. Good to know, if you need or give support from/to others.
This opens up nautilus in the current directory, which is useful for some quick file management that isn't efficiently done from a terminal.
Runs an instance of screen with name of "name_me" and command of "echo "hi""
To reconnect to screen instance later use:
screen -r name_me
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).
connects to all the screen instances running.
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:
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:
# default screenrc on any host
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 -t 'anywhere' /bin/tcsh
screen -t 'anywhere1' /bin/tcsh
The .screenrc-base contains:
## I find typing ^a (Control-a) awkward. So I set the escape key to CTRL-j instead of a.
termcapinfo xterm* ti@:te@:
Have your screen session running in multiple places. (warning, things start to look weird if the terminal windows have different dimensions)
Open a terminal (urxvt in this case) to connect to a screen session (named "main") and create the screen session if necessary.