This command gets a DarkBASIC Pro double
integer from the specified packet. Typically double integers are 8 bytes
in size and range from -9,223,372,036,854,775,808 to +9,223,372,036,854,775,807.
The data will be taken starting at the cursor position and the cursor will be moved forward by the size of the data returned.
long long int Packet: This is the packet that the command should use.
Data from the specified packet if no
error occurred.
0 if an error occurred.
DBP