Detect CTRL-C

BlitzMax Forums/BlitzMax Beginners Area/Detect CTRL-C

Sub_Zero

(Posted 2013) [#1]

Is it possible to detect CTRL-C being pressed from a commandline app?

Brucey

(Posted 2013) [#2]

You can add a signal handler for SIGINT, on unixy platforms, and something like a SetConsoleCtrlHandler() on Windows.

Sub_Zero

(Posted 2013) [#3]

How do i add a signal handler?

col	(Posted 2013) [#4]

Hiya,

There are a couple of ways on Windows. I only know a Windows solution, maybe Brucey or someone else would help out with the other platforms?

This is a simple example that uses SetConsoleCtrlHandler to handle the CTRL-C :-

Strict

' Run the generate .exe to test. This won't work when run from the IDE !!

Extern"Win32"
	Function SetConsoleCtrlHandler(Routine:Byte Ptr,Bool)
EndExtern

If Not SetConsoleCtrlHandler(ConsoleHandler,True) Print "Unable to change console handler"

Repeat
	Delay 1
Forever

Function ConsoleHandler(dwCtrlType)"Win32"
	If dwCtrlTYpe = 0
		Print "CTRL-C detected"
		Return True ' Tell windows that we have handled this
	EndIf
EndFunction

To test it you need to run the final generated exe. It won't work when the code is run from the IDE as the IDE thread picks up the CTRL-C and will terminate anyway. Use the close icon to close the console window.

Hope it helps!