An object handler DLL must have the following functions as part of its structure:
LibMain function (required entrance point for all DLLs)
WEP function (required exit point for all DLLs)
Object-creation callback functions (DllCreate, DllCreateFromClip, and so on)
Function to copy OLEOBJECTVTBL
Object-manipulation callback functions
Any other functions that are used inside the DLL
The following sections provide details on the special functions that must be in the object handler DLL.