title: Boost Log severity levels versus syslog severity levels
body: <p>I'm trying to modify my application to use the Boost Log library instead of logging into <code>syslog</code>. Boost Log severity levels are defined in <code>boost/log/trivial.hpp</code>, where the most serious level has <strong>maximal</strong> numeric number (5):</p>
  
  <pre><code>enum severity_level
  {
      trace,
      debug,
      info,
      warning,
      error,
      fatal
  };
  </code></pre>
  
  <p>However, the <a href="https://en.wikipedia.org/wiki/Syslog" rel="nofollow noreferrer"><code>syslog</code></a> defines more severity levels, which are actually standardized by the <a href="https://www.rfc-editor.org/info/rfc5424" rel="nofollow noreferrer">RFC5424</a> - and most serious level has <strong>minimal</strong> numeric number (0).</p>
  
  <p>Is it any way to define my own <code>MySeverityLevels</code> enumeration type (probably close to the RFC5424) and use various Boost Log loggers (<code>severity_logger</code>, for instance) with this new type, including the filtering by severity level?</p>