title: How can I use grep and regex to match a word with specific length?
body: <p>I'm using Linux's terminal and i've got a wordlist which has words like:</p>
  
  <pre><code>filers
  filing
  filler
  filter
  finance
  funky
  fun
  finally
  futuristic
  fantasy
  fabulous
  fill
  fine
  </code></pre>
  
  <p>And I want to do a grep and a regex to match the find words with the first two letters "fi" and only show the word if it's 6 characters in total.</p>
  
  <p>I've tried: </p>
  
  <pre><code>cat wordlist | grep "^fi" 
  </code></pre>
  
  <p>This shows the words beginning with fi.</p>
  
  <p>I've then tried:</p>
  
  <pre><code>cat wordlist | grep -e "^fi{6}"
  cat wordlist | grep -e "^fi{0..6}" 
  </code></pre>
  
  <p>and plenty more, but it's not bring back any results. Can anyone point me in the right direction?</p>