The GetFileName method returns the current item's file name, with the full path in Universal Naming Convention (UNC) format.
HRESULT GetFileName( WCHARwszFileName, DWORDdwSize, DWORD*pdwLength);
[out, length_is(*pdwLength), size_is(dwSize)] Pointer to a WCHAR that contains a string buffer where file name will be written.
[in] Pointer to a DWORD that contains the size of the wszFileName string buffer.
[out] Pointer to a DWORD that contains the number of characters written to the wszFileName string buffer.
For a list of error messages returned by SharePoint Portal Server Protocol Handlers, see Error Messages.
If this method is implemented, the Filter Daemon will use the filename to access the file directly instead of binding to the stream.
To see this method in a fuller context, see Protocol Handler Sample.