title: Sed with multiple criteria
body: <p>I have 3 <code>sed</code> commands:</p>
  
  <pre><code>sed -n 's/.*domain=\([^&amp;]*\).*sdk_ver=\([^&amp;]*\).*/\1 \2/p' inputfile &gt; outputfile
  sed -n 's/.*sdk_version=\([^&amp;]*\).*domain=\([^&amp;]*\).*/\2 \1/p'  inputfile &gt; outputfile
  sed -n 's/.*domain=\([^&amp;]*\).*sdk_version=\([^&amp;]*\).*/\1 \2/p' inputfile &gt; outputfile
  </code></pre>
  
  <p>Each command has a criterion in it. I just want to put 3 commands into 1 command, to get a single output file which includes all the results as a union of the three criteria.</p>