# File lib/genome-lib/virsh.rb, line 89
    def autostart_disable(opts={})
      name = opts[:domname].nil? ? get_name(opts[:uuid]) : opts[:domname]

      # popen3 doesn't capture the exist status because of the way it spawns
      # the child process
      IO.popen("virsh autostart --disable #{name} 2>&1") do |io|
        yield(io) if block_given?
      end

      if $?.exitstatus != 0
        # We're probably running Xen.  
        if File.exist?("/etc/xen")
          FileUtils.rm_rf("/etc/xen/auto/#{name}") # in case this machine already existed
        end
      end
    end