title: Checking if command response does not contain str
body: <p>I have a script which works great... but I'd like it not do anything if there is no one online. I looked over all the documentation on how to check if a str is not within a variable, but it always thows the same error, which I assume may be something else, but literally nothing else is touched besides the addition of the fi at the bottom for the new if statement to check if there is no users online... </p>
  
  <p>Error: <code>startAnnouncement.sh: 44: [[: not found</code></p>
  
  <pre><code>#!/bin/bash
  
  checkServer=$(/etc/init.d/minecraft status)
  checkUsers=$(/etc/init.d/minecraft command list)
  cd /.smc
  
  # Is the server even running?
  if [[ $checkServer =~ "is running" ]]; then
  
      #Is anyone online to even see the message...?
      if [[ ! $checkUsers =~ "are 0 out" ]]; then
  
         # No count file? Create it.
          if [ ! -f /.smc/lastAnnouncement.txt ]; then
              echo 0 &gt; /.smc/lastAnnouncement.txt
          fi
  
          # Load count
          lastAnn=$(cat /.smc/lastAnnouncement.txt)
  
          # ANNOUNCEMENTS
          announcement[0]='Dont  forget to check out http://fb.com/pyrexiacraftfans for news and updates'
          announcement[1]='Use our Facebook page to request land protection! Visit http://fb.com/pyrexiacraftfans'
          announcement[2]='Stay tuned for the announcement of our spawn build competition soon on our Facebook page!'
          announcement[3]='We have upgraded the server with mcMMO and Essentials Economy! Stay tuned for shop openings!'
  
          announcementText=${announcement[$lastAnn]}
  
          # Send announcement
          sendAnnouncement=$(/etc/init.d/minecraft command say $announcementText)
  
          # Next announcement count
          ((++lastAnn))
  
          # Write next announacment count
          # Should we restart announcement que?
          if [ $lastAnn -gt $((${#announcement[@]}-1)) ]; then
                  echo 0 &gt; /.smc/lastAnnouncement.txt
          else
                  echo $lastAnn &gt; /.smc/lastAnnouncement.txt
          fi
  
      fi
  
  fi
  </code></pre>