title: PHP regular expression to match lines starting with a special character
body: <p>I have a text file with some configuration value. There a comment starts with a #
  I am trying to find a regular expression pattern that will find out all the lines that start with a #</p>
  
  <p>So, sample file:</p>
  
  <pre><code>1st line
  #test line this 
  line #new line
  aaaa #aaaa
  bbbbbbbbbbb#
  cccccccccccc
  #ddddddddd
  </code></pre>
  
  <p>I want to find</p>
  
  <pre><code>#test line this 
  #ddddddddd
  </code></pre>
  
  <p>because only these two lines start with #
  I tried the following code:</p>
  
  <pre><code>preg_match_all("/^#(.*)$/siU",$text,$m);
  var_dump($m);
  </code></pre>
  
  <p>But it always outputs empty array. Anyone can help?</p>