fyi, although it can be done more cleanly (both code and output), I flip off my GPS and back on again, and within three seconds (literally), I achieve lock on four sats:

use warnings;
use strict;

use GPSD::Parse;

my $gps = GPSD::Parse->new;

$gps->poll;

my $sats = $gps->satellites;

for my $sat (keys %$sats){
    if (! $gps->satellites($sat, 'used')){
        print "$sat: unused\n";
    }
    else {
        print "$sat used:\n";
        for (keys %{ $sats->{$sat} }){
            print "\t$_: $sats->{$sat}{$_}\n";
        }
    }
}
[download]

Output:

17: used
    az: 67
    el: 74
    used: 1
    ss: 15
3: unused
11: unused
19: unused
22: unused
24: unused
28: used
    az: 99
    ss: 14
    el: 36
    used: 1
30: unused
13: used
    el: 6
    used: 1
    ss: 13
    az: 220
12: unused
6: used
    az: 165
    used: 1
    el: 30
    ss: 23
15: unused
1: unused
[download]

I have 100% test coverage between the cases that I'm using a socket (actual GPS), or replaying with a saved output file. I've got the docs in order, and have added a couple of examples. Usually it takes me a bit more time for a v1.00 release, but this was a very quick turnaround and I'm very happy with the results. I've tested the code on four machines; two Pi's one with a GPS, the other without, and same with two laptops (one with, one without). I'm just cleaning things up, and then I'm ready to move on to the video camera project. After that, I may consider actually constructing something.