title: How to start thin on the default port?
body: <p>I'm learning thin server, by now I can use <code>thin start</code> to fire up the server, but the port is 3000, I should type the localhost:3000 in the browser to get the webpage.</p>
  
  <p>I want to take off the 3000 port as we normally do with other site. So I set use the command <code>thin -p 80 start</code> to use the default http port. But I got this error:</p>
  
  <pre><code>root@makserver:~/apps/videosite# thin --port 80 start
  &gt;&gt; Using rack adapter
  &gt;&gt; Thin web server (v1.2.7 codename No Hup)
  &gt;&gt; Maximum connections set to 1024
  &gt;&gt; Listening on 0.0.0.0:80, CTRL+C to stop
  /usr/local/lib/ruby/gems/1.9.1/gems/eventmachine-0.12.10/lib/eventmachine.rb:572:in `start_tcp_server': no acceptor (RuntimeError)
      from /usr/local/lib/ruby/gems/1.9.1/gems/eventmachine-0.12.10/lib/eventmachine.rb:572:in `start_server'
      from /usr/local/lib/ruby/gems/1.9.1/gems/thin-1.2.7/lib/thin/backends/tcp_server.rb:16:in `connect'
      from /usr/local/lib/ruby/gems/1.9.1/gems/thin-1.2.7/lib/thin/backends/base.rb:49:in `block in start'
      from /usr/local/lib/ruby/gems/1.9.1/gems/eventmachine-0.12.10/lib/eventmachine.rb:256:in `call'
      from /usr/local/lib/ruby/gems/1.9.1/gems/eventmachine-0.12.10/lib/eventmachine.rb:256:in `run_machine'
      from /usr/local/lib/ruby/gems/1.9.1/gems/eventmachine-0.12.10/lib/eventmachine.rb:256:in `run'
      from /usr/local/lib/ruby/gems/1.9.1/gems/thin-1.2.7/lib/thin/backends/base.rb:57:in `start'
      from /usr/local/lib/ruby/gems/1.9.1/gems/thin-1.2.7/lib/thin/server.rb:156:in `start'
      from /usr/local/lib/ruby/gems/1.9.1/gems/thin-1.2.7/lib/thin/controllers/controller.rb:80:in `start'
      from /usr/local/lib/ruby/gems/1.9.1/gems/thin-1.2.7/lib/thin/runner.rb:177:in `run_command'
      from /usr/local/lib/ruby/gems/1.9.1/gems/thin-1.2.7/lib/thin/runner.rb:143:in `run!'
      from /usr/local/lib/ruby/gems/1.9.1/gems/thin-1.2.7/bin/thin:6:in `&lt;top (required)&gt;'
      from /usr/local/bin/thin:19:in `load'
      from /usr/local/bin/thin:19:in `&lt;main&gt;'
  </code></pre>