title: parallel check md5 file
body: <p>I have a md5sum file containing lots of lines. I want to use GNU parallel to accelerate the md5sum checking process. In the md5sum, when no file input, it will take the md5 string from stdin. I tried this:</p>
  
  <p><code>cat checksums.md5 | parallel md5sum -c {}</code></p>
  
  <p>But getting this error:</p>
  
  <p><code>md5sum 445350b414a8031d9dd6b1e68a6f2367  testing.gz: No such file or directory</code></p>
  
  <p>How can I parallel the md5sum checking?</p>