From: Raphael Clancy <rafemonkey@...>
Date: 2002-01-31T14:13:43+09:00
Subject: Win32API and dll programming in windows

Can anyone recomend a good reference on Win32API and dll programming in
general? I'm trying to get my head aroud it, but can't seem to make
things work. I decided to start out with a very simple function, which
had the signature: 

float GetDllVersion ();

Looking at tha I can see that it doesn't want any arguments, and should
return a float. Knowing that I try to call it like so: 

dllVer = Win32API.new("NameOfDll", "GetDllVersion", [], 'n')

I use [] for the import array 'cause I'm not passing anything to the
dll, and 'n'for the export because the function should return a number. 
Then I call the function like so:

vers = dllver.call()
puts "version: #{vers}"

I run it, and get "version: 0", and I know from the documentation that
it should be version 1.03. the 0 makes me think that 'vers' never gets
anything put in it at all. Perhaps I'm missing the point of the import
array? should I be passing a 4 byte array to the dll, and letting it put
it's answer in that? did I forget to wave the dead chicken? 

I'm going to go beat on this some more, but any help would be
apreciated! 

Thanks, R.