SIGSTOP does /not/ put a process into background, it does what it says; it stops a process, i.e. the process doesn't use CPU time, while a process in the background (by '&' or 'bg') is of course still running.
Seems like this could be summarized a bit. Let me have a go at it here. From my console I can start an application by typing it's command and it will start. This is a given obviously but needs to be pointed out since everything else is just a modification of sorts of the command. For example, if I wish to start mozilla, I type: jlemay@gambit$>mozilla ..and mozilla starts up (so long as X is running!). If I want to start another program from that same console, I need to stop mozilla first - at least temporarily - by giving the console window focus again and doing a "CTRL-z". I now have a prompt back, but Mozilla seems frozen. It is - kind of. It's actually stopped. I can bring it back by issuing the "bg" command. When I do, Mozilla immediately becomes responsive again since it is no longer stopped. I could actually have started Mozilla (or any other application) and immediately put it in the background by appending " &" at the end of the command like so: jlemay@gambit$>mozilla & Now mozilla starts and I'm presented with my prompt again. Completed three steps with one command this time. The "fg" command would bring Mozilla back to the foreground relative to the console and my prompt would be inaccessible again. I think that explains backgrounding processes pretty well. I suppose "nohup" might also be helpful, but since I've never used it I'll leave that up to someone else to discuss if an explanation is needed. -- John LeMay KC2KTH Senior Enterprise Consultant NJMC | http://www.njmc.com | Phone 732-557-4848 Specializing in Microsoft and Unix based solutions -- John LeMay KC2KTH Senior Enterprise Consultant NJMC | http://www.njmc.com | Phone 732-557-4848 Specializing in Microsoft and Unix based solutions