title: File property in RollingFileAppender - logback Configuration
body: <p>I have the following RollingFileappender in my logback configuration file.</p>
  
  <pre><code>&lt;appender name="RollingFILE" class="ch.qos.logback.core.rolling.RollingFileAppender"&gt;
    &lt;File&gt;C:\Files\MyLogFile.log&lt;/File&gt;      
    &lt;rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy"&gt; 
      &lt;FileNamePattern&gt;C:\Files\MyLogFile.%d{yyyy-MM-dd}.log&lt;/FileNamePattern&gt;       
      &lt;MaxHistory&gt;30&lt;/MaxHistory&gt;     
    &lt;/rollingPolicy&gt;      
    &lt;encoder&gt;
      &lt;pattern&gt;%date %level [%thread] %logger{60} [%file:%line] %msg%n&lt;/pattern&gt;
    &lt;/encoder&gt; 
  &lt;/appender&gt;
  </code></pre>
  
  <p>It does write to MyLogFile.log but does not append the date as specified in the FileNamePattern.</p>
  
  <p><em>There is a <a href="https://stackoverflow.com/questions/10953915/filenamepattern-in-rollingfileappender-logback-configuration">simular question</a>, but it never answered my confusion.</em></p>
  
  <p>I should omit the file property.
  <strong>Why is the file-property then usefull</strong>, because it seems to overrule the rolling-file activity.</p>
  
  <p>This confuses me. Did is get something wrong?</p>