title: mlton view intermediate C file when using `-codegen c`
body: <p>I have the following SML source file with a trivial function in it:</p>
  
  <pre><code>(* fact.sml *)
  fun fact_unguarded 0 = 1
    | fact_unguarded n = n * fact_unguarded(n-1)
  
  fun fact 0 = SOME(1)
    | fact n = if n &gt; 0 then SOME(n * fact_unguarded(n-1)) else NONE
  </code></pre>
  
  <p>I'm trying to compile it with MLTon using the C backend and look at the generated C code.</p>
  
  <pre><code>% mlton -codegen c fact.sml
  </code></pre>
  
  <p>However, none of the intermediate files are dumped in the current working directory and there appears to be nothing relevant in <code>/tmp</code> either. Is there a way to direct MLTon to either a) produce just the C source file and stop or b) keep intermediate files around even after the final artifact is produced.</p>
  
  <pre><code>% pwd
  ~/tmp/sml
  % ls
  fact*       fact.sml
  </code></pre>