Messenger Plus! is programmed in Visual Studio
7.1 2005 and is developped entirely in C++ and some small bits of assembler.
It uses many Windows APIs. In fact if there where no Windows APIs, Plus! wouldn't be possible (just as extremely many other applications wouldn't be possible).
This is also the reason why there will be no Plus! for other operation systems. Eg: On the Mac there are no APIs, and therefore a program like Plus!, programmed like Plus!, isn't possible on that. Same with Linux, etc... On other operating systems a program like Plus! must be programmed in an entirly different way (if at all possible).
It also uses MSN Messenger APIs of course. And again, without the MSN Messenger APIs it would be almost impossible todo what Patchou has done. Thus, no Plus! for the Mac version of MSN Messenger as that version doesn't have APIs....
It would be to much to list all the used Windows API's though, there are way too many.
If you want to find out more on Windows API's, I'd suggest to take a look at the
MSDN library.
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