The OnUpload event handler is invoked after the client has
successfully uploaded a file to the server using the APPE, STOR or
STOU command. To implement
an event handler, the application should create a class derived from
the CFtpServer class, and then override this method.
The ULARGE_INTEGER structure is actually a union that is used to
represent a 64-bit value. If the compiler has built-in support for
64-bit integers, use the QuadPart member to access the 64-bit
integer value. Otherwise, use the LowPart and HighPart
members to access the value.