title: mkdir: cannot create directory ‘data’: File exists
body: <p>This is a simple question, but it is not working. The following script (fol.sh):</p>
  
  <pre><code>if [ -d data]; 
  then 
     echo "exists"
  else
     mkdir data
  fi
  </code></pre>
  
  <p>Return:</p>
  
  <pre><code>./MergeData.sh: 1: [: missing ]
  mkdir: cannot create directory ‘data’: File exists
  </code></pre>