[ gpsdrive ] External program interfacing with gpsdrive

[stan]

Sent this yesterday but got my email addresses mixed up so it may have gone to 
the bit bucket, sorry if it's a duplicate.

New to the list, hi to all. Not used gpsdrive for a while. Wow, great work, 
very impressive. OSM has made a world of difference and the usage figures at 
openstreetmap suggest the whole world will be covered in detail quickly with 
so many folks involved and more every day.
Anyway, I'm going off track, my question is:
Is there any way for an external program to send track files to gpsdrive? My 
thinking is this, something to read the current position, to read the 
destination and to plot a track using the postgres osm data, then send it to 
gpsdrive.
I'm jumping the gun a bit as there is a mountain of work needed, the track file 
is just the final link in the chain but it may also be of use to others. 
Gpsdrive refreshes as it reads the current gps position, is it also possible 
to re-read a loaded track file so if the file is updated so is the path?
Also, any suggestions for tools and libs to read the osm data? Perl for my own 
preference but libs currently used by gpsdrive would be the best thing if 
integration ever came up.
cheers,
Stan

To add a bit more, I spent yesterday reading up on a few alternatives 
including pgrouting. It looks like most of the calculations work has already 
been done but the documentation for pgrouting isn't exactly novice friendly 
(or I'm a bit thick ;) ). I can't figure out one simple thing, does it need to 
re-write the entire OSM psql database to work? Thats 2 databases in total, the 
map data and the routing data?
For now I need to learn some more about the database so will concentrate on a 
simple search for streets and locations and try to figure out how to build it 
in to gpsdrive.
Cheers