[fpc-pascal] Windows find out if an application already is running

[Frank Peelo]

Fantomas wrote:
> Hello, Rainer!
> 
> Sunday, March 15, 2009, 10:22:04 PM, you wrote:
> 
> 
>>I tried system.hprevinst, but this shows always 0.
>>If there are more copys of the program then hinstance is always the same 
>>value.
> 
> 
> hPrevInst does not work under Win32. It is only for Win16, AFAIK. Use a named
> mutex, as it was given, or a named event. Also, you can find a window created by
> the previous instance by its class name.

There is a technique presented at
http://www.flounder.com/nomultiples.htm
It's not in Pascal, but the same technique should work in any language.