title: awk to print line greater than zero in column 1
body: <p>I am trying to print the name of directories whose free space is greater than zero. </p>
  
  <pre><code>  #Listed all the directory and their consumed space.
      du -sm storage*
      365     storage1
      670     storage2
      1426    storage3
  </code></pre>
  
  <p>I have threshold value of 1000M , so I am trying to print free space in these directories relative to threshold value provided. </p>
  
  <pre><code>du -sm storage* | awk -v threshold="1000" '$1&gt;0{print $1=threshold-$1,$2}'
  635 storage1
  330 storage2
  -426 storage3
  </code></pre>
  
  <p>So , I want to print those directories whose free size is positive integer. Something like :</p>
  
  <pre><code>635 storage1
  330 storage2
  </code></pre>
  
  <p>Any correction ?</p>