Are there such tings like custom signals?

[Manuel Ferrero <mferrero reer it>]

I'm learning GTK+ and I was able to write, compile and run a simple code 
on my win32 PC to create a window with a button in it and monitor with a 
callback if the user presses the button.
I learned that GTK+ reacts to user events signalling on the object that 
received the event.

Now I'd like to execute some custom code when the button is pressed, 
i.e. I'd like to open a COM port and send some strings on it and then 
wait for an answer.
I was wondering if there is some custom signal I can use to keep the 
same event-driven philosophy to exchange messages between process.

Maybe the question is not well placed, I'm really newbie on this 
programmation style, I'm an embedded C developer so I don't know a lot 
about GUI and OSes...

TIA

GTK+ 2.24.8
Windows XP
--
Regards,
Manuel Ferrero
R&D department

Reer SpA        
Tel.  +39 011 2482215
Fax. +39 011 859867

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