Take the 2-minute tour ×
Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free, no registration required.

I have created a screen, but can I now somehow execute a command that will run commands in the detached screen?

I do not even know if this is possible, but if it is, it will probably be something simple and easy for you.

Thank you for your effort.

share|improve this question

2 Answers 2

Note: The original poster asked 'how can i do this in cron'. I've updated the response to address that.

  • Get the 'inscreen' script and put it in ~/bin/:

    # download 'inscreen' script from https://gist.github.com/1019125
    wget -O ~/bin/inscreen https://gist.github.com/gists/1019125/download
    chmod 755 ~/bin/inscreen
    
  • create a screen session named 'cronjobs':

    screen -d -m -S cronjobs

    You'll have to arrange for that to happen on each boot, or add '--new-if-needed' to each crontab entry below.

  • Add entries in cron using inscreen, crontab looks like:

    PATH = /home/YOURNAME/bin:/usr/sbin:/usr/bin:/sbin:/bin
    
    * * * * * inscreen cronjobs -- sh -c 'echo $(date): start; sleep 30; echo $(date): end; sleep 4'
    0 0 * * 0 inscreen cronjobs --keep-open --title reminder echo ==== CALL YOUR MOM ====
    0 0 * * 1 inscreen cronjobs --window 0 ls /tmp
    

The above will:

  • every minute open a new window in the 'cronjobs' screen session that writes the date, sleeps for 30 seconds and then exits. The window will close on exit.
  • every sunday at midnight open a new window with title 'reminder' that says "==== CALL YOUR MOM ====" and requires you to hit enter to close the window.
  • every monday at midnight run 'ls /tmp' in the first window of the 'cronjobs' session. Note, though, that no other '--window 0' jobs can be running at the same time.
share|improve this answer
    
how does this work with cron? When I am calling screen -X stuff $FOO from the shell it works as a cronjob it seems to have no effect... –  user10893 Feb 16 '11 at 8:51

smoser's answer is good though a little complex. You can also just simplify this to just

screen -d -m -S mysession -t label sleep 1m

with the caveat that, when the process exits, the screen will just disappear, and you won't be able to see what it wrote to the screen. That might or might not be ok for your case. You can change that by setting in your .screenrc

defzombie ZZ 

which will mean that screens hang around after their process exits until you press Z.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.