#!/usr/bin/ruby

# save as 'hosts.rb'
# put the sites you want to block in the section below __END__
# ruby with 'sudo ruby hosts.rb'

new_hosts = ' '+DATA.read.split("\n").join(' ')
hosts = open('/etc/hosts') {|fh| fh.map {|s| s.chomp } }
hosts.each_with_index {|h,i| hosts[i] = "127.0.0.1 localhost #{new_hosts}" if h =~ /^127\.0\.0\.1/ }
print "blocking #{new_hosts}..."
`cp /etc/hosts /etc/hosts.bak`
open('/etc/hosts', 'w') {|fh| fh.puts(hosts) }
puts "done."

__END__
foo.com
bar.com