where are windows API functions defined?

when you need to use a function you include a header file b开发者_StackOverflowut wheres the function code is defined?

Dave, the code lives in the various and many DLL files in your Windows\system32 directory.

The actual code that implements the Win-32 API are defined in various DLLs on your system. These DLLs have names like kernel32.dll, comctl32.dll etc. You will find them in C:\Windows\System32.

What generally happens is that you link your code with kernel32.lib etc. that have a little code to dynamically load the DLLs when your program starts. This allows Win32 API functions to directly call into the DLLS.

Well as explained above you are in the hands of microsoft. You can always look at the msdn http://msdn.microsoft.com. For most API functions you can find some information at the bottom. For most function you get from there:

Minimum supported client
Minimum supported server
Header
Library
DLL
Unicode and ANSI names