When the initscript is called gpsdate it might kill itself before
it has a way to start the new gpsdate process. Use pidof with the
full path to the gpsdate binary to avoid this.
The easiest way would be to use start-stop-daemon and let it
daemonize the process and create a pid file. Because all of this
is not there and the application unconditionally daemonizes itself
I can just use killall to stop it.