From: Steve Tuckner <STUCKNER@...>
Date: 2003-12-06T01:53:05+09:00
Subject: Re: Win32API: FindWindow

Oops....never mind :-(

> -----Original Message-----
> From: Steve Tuckner [mailto:STUCKNER@MULTITECH.COM]
> Sent: Friday, December 05, 2003 9:29 AM
> To: ruby-talk ML
> Subject: Win32API: FindWindow
> 
> 
> We are having trouble running a Win32 function to find if a 
> window class
> is currently registered (so we can see if our app is already running).
> We use the Win32 function FindWindow to check for the existence of the
> window class. When we do it in Ruby with Win32API, it doesn't work but
> if we write a simple C app it does work. Below are the code fragments.
> Any ideas?
> 
> Here's the C code that works for detecting the existence of 
> the client's
> window handle given its window class and name:
> 
> if ((hwnd = FindWindow("simplewin00041943040000::faxfinderclass",
> "FaxFinder Fax Client Software")) != 0)
>     strcpy(szResult, "FaxFinder Application Found");
> else
>     strcpy(szResult, "FaxFinder Application Not Found");
> DrawText(hdc, szResult, strlen(szResult), &rt, DT_CENTER);
> 
> Here's the Ruby code fragments to try and achieve the same thing
> 
> $FindWindow = Win32API.new("user32","FindWindow",["p","p"], "L")
> if (hwnd = $FindWindow.call("simplewin00041943040000::faxfinderclass",
> "FaxFinder Fax Client Software")) != 0 then
>     mainDisplay.messageBox("FaxFinder Client Software already running
> (look in system tray)", "ERROR")
>     return
> end
> 
> In the above case, some non-zero window handle is always received,
> whether the app is running or not.
> 
> Steve Tuckner 
> 
> 
>