title: Error "tar: Invalid transform expression"while I am creating a TAR using system command in ruby. Why?
body: <p>I am creating a TAR using system command in ruby, passing a array as argument<br>
  which look likes this: <br></p>
  
  <pre><code>cmd_params = ["tar", "-cf", "my.tar", "wp-signup.php_1433243457_25152", "--transform='s/_[0-9]*_[0-9]*$//g'"]
  system(*cmd_params)
  </code></pre>
  
  <p>But getting an Error </p>
  
  <blockquote>
    <p>tar: Invalid transform expression</p>
  </blockquote>
  
  <p>is there any way out for doing this ??</p>