title: Separate build directory using xcodebuild
body: <p>The man page for <code>xcodebuild</code> reads:</p>
  
  <blockquote>
    <p>Run xcodebuild from the directory
    containing your project (i.e. the
    directory containing the
    projectname.xcodeproj package).</p>
  </blockquote>
  
  <p>I would like to keep my source directory (which is a Subversion external) clean and unmodified, and build my object files and executables to a location completely outside of the source directory.</p>
  
  <p>Is there any way to build into a separate build directory from a terminal using <code>xcodebuild</code> like you can do with <code>make</code> tools or even <code>msbuild</code> on Windows?</p>