How I can convert planet file 0.3 to 0.6

Planet files of versions 0.3 and 0.4 had a very different data model; instead of ways that consisted of nodes, they had ways which consisted of segments and those, in turn, consisted of nodes. There are several issues with representing these files in today's data format:

• segments that are not used by any ways require special handling (should they be converted to pseudo-ways, or ignored?)
• segments could have tags; but what would one make of those tags when converting a 0.6-style way?
• in 0.3/0.4 it was possible to have non-contiguous ways; areas with holes were formed by a way that had both the outer and the inner ring's segments.

So when converting data from that old format, there's no clear-cut way and you will have to make some decisions.

There is a script that can do the conversion here:

http://svn.openstreetmap.org/applications/utils/conv05/04to05.pl

(despite the name, it should be safe for 0.3 also). I have also uploaded an old (060814) planet file which has already been converted to 0.6 format here:

http://www.remote.org/frederik/tmp/planet-060814-converted-to-06.osm.bz2