title: How to use ldid?
body: <p>I am trying to run unsigned application on iOS 5.1/iPhone 4s (jailbroken). What I did:</p>
  
  <ol>
  <li><p>Disable code signing in XCode.</p></li>
  <li><p>Built unsigned iPhone app.</p></li>
  <li><p>Copied it to my iPhone via SSH to location /User/me/development/HelloWorld.app</p></li>
  <li><p>Now I try to simulate its signing to run this application on iPhone. I run follwing commands:</p></li>
  </ol>
  
  <p>.</p>
  
  <pre><code>cd /User/me/development
  chmod -R 777 HelloWorld.app
  ldid -S HelloWorld
  </code></pre>
  
  <p>However, I receive following error:</p>
  
  <pre><code>util/ldid.cpp(567): _assert(78:arch != NULL)
  </code></pre>
  
  <p>What are possible reason of such error and now to fix it?</p>