title: sed command creates randomly named files
body: <p>I recently wrote a script that does a sed command, to replace all the occurrences of "string1" with "string2" in a file named "test.txt".</p>
  
  <p>It looks like this:</p>
  
  <pre><code>sed -i 's/string1/string2/g' test.txt
  </code></pre>
  
  <p>The catch is, "string1" does not necessarily exist in test.txt.</p>
  
  <p>I notice after executing a bunch of these sed commands, I get a number of empty files, left behind in the directory, with names that look like this:</p>
  
  <p>"sed4l4DpD"</p>
  
  <p>Does anyone know why this might be, and how I can correct it?</p>