gpsctl is a utility program written for Raspberry Pi computers using a U-Blox GPS board. The author's rig is a Raspberry Pi 3 Model B with a Uputronix GPS board, which uses a U-Blox MAX-M8Q GPS module. Some of gpsctl's functions are generic for any GPS that streams NMEA data to a Linux serial port, and these should work on any Linux system. Most of gpsctl's functions, however, are quite specific to the U-Blox products, and use their proprietary UBX protocol (again, on a serial port).
Found on https://thepihut.com/products/raspberry-pi-gps-hat