title: How to install GNU flex or lex on Raspbian Raspberry
body: <p>I need to install <a href="http://www.eyedb.org/" rel="nofollow">EyedDB</a> for studies and I'd like to run it on my Raspbian Raspberry.
  I downloaded and unzipped at <code>/usr/programs/EyeDB</code> where I ran first with Pi user as requested and later as root:</p>
  
  <pre><code>./configure
  </code></pre>
  
  <p>Then a bunch of lines is coming out and ended with</p>
  
  <pre><code> error: you must have Gnu flex or lex installed to compile EyeDB
  </code></pre>
  
  <p>Any clues?</p>