There's recently been a
long running thread in which xj25vm has explored the possibilities of getting gpsd to start on demand in Slackware, both when USB GPS devices are hotplugged (plugged into an already booted system) and when coldplugged (discovered by the system at boot).
The core difficulty to be overcome was that the gpsd daemon wants to read from a control socket which is created on the fly by a helper when the hotplugged or coldplugged device triggers an action in udev....
