How to keep running program after SSH logout without screen

gigam · 11-03-2012, 02:07 PM

Hello everyone.
I am logged into a computer through ssh. I would like to run a program and have it keep running after I log out without screen (i forgot to run it).

For example:
ssh server
user/comp~$ top &
[1] 12021
exit

after that:
ssh server
user/comp~$ (something, maybe shell script) 12021

How can I do that except disown solution?

acid_kewpie · 11-03-2012, 03:39 PM

you forgot to run screen? why not just run it now?? that is the perfect solution, and I'm not aware of anything else that would be suitable.

archShade · 11-03-2012, 03:53 PM

check out nercshttp://caca.zoy.org/wiki/neercs

acid_kewpie · 11-03-2012, 04:22 PM

Hmm, not sure how "screen + pointless gimmicks" is going to be better than just using screen.

archShade · 11-03-2012, 04:40 PM

From linked website emphasis mine

Quote:

neercs is a work-in-progress libcaca project.

Like GNU screen, it allows you to detach a session from a terminal, but provides unique features:

Grabbing a process that you forgot to start inside neercs
Great screensaver
3D rotating cube to switch between full screen terms
Real time thumbnails of your shells
Special effects when closing a window
Various window layouts...

Yes there are ways to do this with screen but they all seem to be a bit of a hack.

I agree all the other stuff seems just to be a good way burn cpu cycles

gigam · 11-03-2012, 04:46 PM

Quote:

Originally Posted by acid_kewpie

you forgot to run screen? why not just run it now?? that is the perfect solution, and I'm not aware of anything else that would be suitable.

It's a hack-task: I have a process, and i need to detach it from a tty1 and attach to my recent tty2. Or relogin to ssh service and attach it in my current session and continue working with it.

Quote:

Grabbing a process that you forgot to start inside neercs

Yeah, that's it! But it's a custom solution, it's not solution by OS environment.
And the problem is: how to do that without external applications?

acid_kewpie · 11-03-2012, 04:48 PM

Heh, well that neercs program does actually say it can grab an existing process, so maybe I look a bit silly now...

gigam · 11-03-2012, 04:58 PM

Quote:

Originally Posted by acid_kewpie

Heh, well that neercs program does actually say it can grab an existing process, so maybe I look a bit silly now...

Well, I have an example of solution, but it has it's own drawbacks:

Code:

#!/usr/bin/bash 
while [ true ]
do
sleep 1
echo "I'm alive"
done

Code:

ps aux|grep deatachme.sh|grep -v grep| awk '{print $2 }' 
tty  
ls -l /proc/$PID/fd //output process's file descriptors
touch stdout
touch stderr
gdb -p $PID

in gdb:

Code:

p close(1) //close stdout
p open("/home/user/stdout", 1)
p close(2) //close stderr
p open("/home/user/stderr", 2) 
q //quit

in the terminal with living process: Ctrl+Z

Code:

bg %1 && disown %1

ctrl+d
echo "hello" > /proc/$PID/fd/0

larvel · 11-03-2012, 05:54 PM

What about "nohup command"?

gigam · 11-03-2012, 06:13 PM

Quote:

Originally Posted by larvel

What about "nohup command"?

You need to use nohup before command is running.
This solution contradicts to the terms of the problem.

gigam · 11-04-2012, 06:39 AM

Quote:

Originally Posted by archShade

From linked website emphasis mine
Yes there are ways to do this with screen but they all seem to be a bit of a hack.

Well, tell me, please, about theese ways