gistfile1.rb

require 'rubygems'
require 'OSM'
require 'OSM/StreamParser'
require 'OSM/Database'


class CustomCallback < OSM::Callbacks

  def node(node)
    @node = node
  end
  
  def way(_way)
  end
  
  def relation(_relation)
    puts _relation
  end
  
  def result
    @node
  end
  
end

cb = CustomCallback.new
parser = OSM::StreamParser.new(:filename => 'bahrain.osm', :callbacks => cb)
puts parser.parse

#
#db = OSM::Database.new
#parser = OSM::StreamParser.new(:filename => 'bahrain.osm', :db => db)
#
#puts db.nodes.size