On 10/27/06, Darryl Palmer <<a href="mailto:dpalmerjr@gmail.com">dpalmerjr@gmail.com</a>> wrote:<div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> On 10/27/06, David Trask <<a href="mailto:dtrask@vcsvikings.org" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">dtrask@vcsvikings.org</a>> wrote: <div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> How could one write a script that could then become a launcher or menu item that would poll the system to see if that program was already running under the logged on user....if not....then launch the program....if yes....then abort. This might make it easier to keep kids from going "click happy" and opening multiple instances of a program. Any ideas? </blockquote></div> You can use lockfile to do this, you can write something like #! /bin/bash #Check to see if the lockfile exits if lockfile -! -r 0 ~/.locks/lockfile-firefox; then echo "Unable to start firefox, lock file exists" exit 1 fi firefox rm -f ~/.locks/lockfile-firefox </blockquote></div> While this implementation is nice, it does have the problem of the lockfile not being deleted when programs/apps crash. Using ps would be better. You can try something like #! /bin/bash count=`ps | grep firefox | grep -v grep | wc -l | awk '{print $1}'` if [ ! $count -eq "0" ] then echo "Unable to start firefox, already running!" exit 1 fi firefox Darryl