gpsd is a service daemon that monitors one or more GPSes attached to a 
host computer through serial or USB ports, making all data on the location, 
course, and velocity available to be queried on TCP port 2947 of the host 
computer.  With gpsd, multiple GPS client applications (such as navigational 
and wardriving software) can share access to GPSes without contention or 
loss of data.  Applications that presently use gpsd include Viking and Kismet.

See README.build for some additional build options that might be useful.