Data has been sent to the GPS receiver
Parameters passed to GPSNOTIFYPROC:
lParam1
The number of bytes sent to the GPS device.
lParam2
A pointer to a NULL-terminated text status message: "Data has been sent to the GPS device". On Windows CE platforms this will be a Unicode buffer; on all other platforms it is an ASCII buffer.
lParam3
Contains the user-defined parameter lUserParam that was passed to the
GpsSetNotificationCallback function.