[baker-baker] sandbox compile

[T. Onoma]

Here is chroot as given in rubyx. There are a couple of things I'm wondering 
about it. A) proc is mounted B) nearly all ENV variables are deleted and then 
reconstructed from /etc/enviornment (albiet my evironment file is empty) and 
C) it is all run in a separate process.  Are these neccessary?

def chroot(dir)
  User.asroot {
    raise "mount proc failed" unless system("mount -n -t proc proc 
"+path(dir,'proc'))
    begin
      trap('INT','IGNORE')
      pid = Process.fork {
        begin
          dir.cd #MUST cd before chroot - see Dir.chroot docs
          Dir.chroot(dir)
          #Reset the rubyx UID/GID which may be different here
          User.set($users['rubyx'],$groups['users'])
          $root = '/'
          #ENV.delete_if { |key,val| key!='TERM' }
          '/etc/environment'.fread.each { |v| v =~ /export (.*)=(.*)/; 
ENV[$1]=$2 }
          ENV['HOME'] = '/home/root'
          yield
        rescue Exception
          puts $!
        end
      }
      Process.waitpid(pid)
    ensure
      system('umount -ln '+path(dir,'proc'))
      trap('INT','DEFAULT')
    end
  }
end


-- 
T.