[OSM-newbies] Setting up mapnik

[Sebastian Mauer]

Hello there,

I've built mapnik-0.5.1 debian packages according to
http://wiki.openstreetmap.org/index.php/Mapnik#For_Debian_Etch_.28stable.29_
.28Mapnik_0.5.29
and the resulting debs installed without a flaw.

But after customizing set-mapnik-env and building my own osm.xml there seems
to be a problem
With my mapnik installation as ./generate_tiles.py fails with the following
output:

debian:/var/www/enexigo/mapnik# ./set-mapnik-env  ./generate_tiles.py
render_tiles( (-180.0, -90.0, 180.0, 90.0) /var/www/enexigo/mapnik/osm.xml
/var/www/enexigo/tiles/ 0 5 World )
 got exception ...
Traceback (most recent call last):
  File "./generate_tiles.py", line 126, in ?
    render_tiles(bbox, mapfile, tile_dir, 0, 5, "World")
  File "./generate_tiles.py", line 53, in render_tiles
    load_map(m,mapfile)
RuntimeError: failed opening file: Bad file descriptor

Is there a way to determine which file it tried to open / and why it failed?

Greetings,

Sebastian