Calling an API from an External Business Function

You can call APIs from external business functions. To call an API from an external business function, you must first determine the function-calling convention of the .dll that you are going to use. It can be either cdecl or stdcall. The code might change slightly depending on the calling convention. This information should be included in the documentation for the .dll. If you do not know the calling convention of the .dll, you can execute the dumpbin command to determine the calling convention. Execute this command from the MSDOS prompt window:

 dumpbin /EXPORTS ExternalDll.DLL. 

Dumpbin displays information about the dll. If the output contains function names preceded by _ and followed by an @ sign with additional digits, the dll uses the stdcall calling convention; otherwise, it uses cdecl.