ReadBytes method reads a number of bytes into a buffer.
HRESULT ReadBytes( void *pvBuffer, ULONG cbRequested, ULONG *pcbRead, BOOL *pbEndOfFile );
A pointer to the buffer that the bytes will be read into..
The number of bytes that are requested for the read.
A pointer to the number of bytes actually read.
A pointer to a BOOL value that indicates whether the end of file (EOF) was read.
ReadBytes returns an HRESULT value.