Writing Platform Independent Applications

[This is preliminary documentation and subject to change.]

The first release of Microsoft Active Accessibility supports Microsoft Windows 95 only; however, clients and servers might need to run on Windows NTŪ as well. Active Accessibility introduces new APIs that are not yet available on the Windows NT platform. As a result, instead of relying on import libraries to call new APIs, an MSAA application should use GetProcAddress to dynamically address new USER functions.

For example, an application that wants to use NotifyWinEvent should call GetProcAddress() using the module handle of USER to get the address of the API. If the call is successful, meaning that this version of Windows supports MSAA, then the application can set a flag indicating that it is safe to call NotifyWinEvent. The address received from GetProcAddress() can be stored in a function pointer variable and used throughout the code. See the sample source code for the server application for details.