Hi, 1. "How can I determine what the user responds, is there errorlevels or anything like that?" You can check for the exit status of the xmessage command 2. "What is the reason for doing ' > /dev/null 2>&1'" It redirects any standard out and standard error to oblivion Let's say you have a vnc session on port 5902. You want a script that checks if there's a session and display a message to the user. And you want to know if the user read the message. Here's what you could do. (you'll have to adapt and add a loop in there if you have several vnc sessions) Edit the linux user's ~/.vnc/xstartup and add an "xhost +" in it. Otherwise you will not be able to display the message. Use a script similar to this one: (of course, you will adapt and enhance) #!/usr/bin/env bash netstat -tape | grep ESTABLISHED | grep Xvnc | awk '{print $4}' | awk -F ":" '{print $2}' > log-ports for user in `cat log-ports` do case $user in 5902) export DISPLAY=:2.0; xmessage -buttons "I understand":10 -center -timeout 60 -file testmsg > /dev/null 2>&1 [ $? -eq 10 ] \ && echo "$user acknowledged!" \ || echo "No answer from $user!" ;; esac done The user connected to 5902 will get a windowed message with a "I understand" button. If he clicks on it, you'll know. If he doesn't, it'll time out after 60 seconds and return an exit status of 0 (zero): you'll know too . Hope it helps, Olivier <div>2008/1/31, Henning Larsen <<a href="mailto:hennlar@start.no">hennlar@start.no</a>>:<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> Thanks for the good answer. On Thu, 2008-01-31 at 15:05 +0100, Olivier Robert wrote: > Hi, > > I would check for established VNC connections this way: > > netstat -tape | grep ESTABLISHED | grep Xvnc > > As for warning connected users. If you see there is an established vnc > session on port 5902, you could simply do: > > export DISPLAY=:2.0; xmessage -center -timeout 60 -file shutdown.txt > > /dev/null 2>&1 How can I determine what the user responds, is there errorlevels or anything like that? Hundred years ago I was making a lot of advanced BAT-files in msdos, but have not done much of those things in Linux yet. I could or maybe should find out reading man-pages, but have already asked. :) What is the reason for doing ' > /dev/null 2>&1' > You could create a list of established connections, translate it to > active displays (5902 -> 2.0 | 5903 -> 3.0 ...) and send out a > message. > > Hope it helps > Olivier > It helps a lot, Thanks Henning Larsen -- fedora-list mailing list <a href="mailto:fedora-list@redhat.com">fedora-list@redhat.com</a> To unsubscribe: <a href="https://www.redhat.com/mailman/listinfo/fedora-list">https://www.redhat.com/mailman/listinfo/fedora-list</a> </blockquote></div>