Thread: Intercept instance of the program already running

Hello to everyone,

I am not sure if this is the right place for this type of question ...

I would like to create a program that before displaying the graphical interface, checks if there is already an instance of the same program in execution and if it exists, pass the focus to that instance (in practice, bring it to the front compared to other applications) and terms its execution.

This is because this program, after executing any operation requested by the user, should make itself invisible while remaining in execution, so that at a subsequent run of the same application the invisible instance is simply activated with the aforementioned method.

I realized a similar application when I developed in VB6 obviously only on Windows up to XP.

The application should be totally cross-platform, because I use WinXP, Win7, Win8.1, Kubuntu 14.04, Kubuntu 18.04.

Now I'm using Netbeans (both on Windows and on Kubuntu) as a development tool.

I don't know if I explained myself.

The aim is to speed up the appearance of the program whenever I need it, because the first activation is too slow.

Can anyone give me directions on how to do this?

OK thanks.
I'll have to study how to use sockets.

Now the problem is, how to communicate to the previous executing instance to bring it to the fore.
do you have any indication?

Ok Norm.
Thanks a lot.
So, now I have to study a lot.