我正在学习有关独角兽和 nginx 的 railscasts 教程（http://railscasts.com/episodes/293-nginx-unicorn），在 vagrant 中使用 lucid32 框。我的操作系统是山狮。我正在使用 rbenv 和 ruby 1.9.2p290。将独角兽添加到我的 Gemfile 并运行捆绑包后，我运行：
bundle exec unicorn -c config/unicorn.rb -D
这是结果：
/opt/vagrant_ruby/lib/ruby/gems/1.8/gems/kgio-2.8.0/lib/kgio.rb:21:in `require': /opt/vagrant_ruby/lib/ruby/gems/1.8/gems/kgio-2.8.0/lib/kgio_ext.so: undefined symbol: rb_prohibit_interrupt - /opt/vagrant_ruby/lib/ruby/gems/1.8/gems/kgio-2.8.0/lib/kgio_ext.so (LoadError)
from /opt/vagrant_ruby/lib/ruby/gems/1.8/gems/kgio-2.8.0/lib/kgio.rb:21:in `<top (required)>'
from /opt/vagrant_ruby/lib/ruby/gems/1.8/gems/unicorn-4.6.0/lib/unicorn.rb:6:in `require'
from /opt/vagrant_ruby/lib/ruby/gems/1.8/gems/unicorn-4.6.0/lib/unicorn.rb:6:in `<top (required)>'
from /opt/vagrant_ruby/lib/ruby/gems/1.8/gems/unicorn-4.6.0/lib/unicorn/launcher.rb:9:in `require'
from /opt/vagrant_ruby/lib/ruby/gems/1.8/gems/unicorn-4.6.0/lib/unicorn/launcher.rb:9:in `<top (required)>'
from /opt/vagrant_ruby/lib/ruby/gems/1.8/gems/unicorn-4.6.0/bin/unicorn:3:in `require'
from /opt/vagrant_ruby/lib/ruby/gems/1.8/gems/unicorn-4.6.0/bin/unicorn:3:in `<top (required)>'
from /opt/vagrant_ruby/bin/unicorn:19:in `load'
from /opt/vagrant_ruby/bin/unicorn:19:in `<main>'
有小费吗？