title: sed command to replace first occurrence in file is not working
body: <p>I am trying to replace first string occurrence in file. e.g. Trying to replace first <strong>foo</strong> with <strong>linux</strong></p>
  <p>sample.txt</p>
  <pre><code>Hi foo bar
  This is again foo bar.
  </code></pre>
  <p>Command: <code>sed '0,/foo/s//linux/' sample.txt</code></p>
  <p>Actual output from above command (basically no change)</p>
  <pre><code>Hi foo bar
  This is again foo bar.
  </code></pre>
  <p>My expected output is as below</p>
  <pre><code>Hi linux bar
  This is again foo bar.
  </code></pre>
  <p>Could anyone please help here?</p>