src/Generics/Logger/SimpleLogger.php
protected function logImpl($level, $message, array $context = array())
    {
        if (! $this->levelHasReached($level)) {
            return;
        }
        
        if ($this->isRotationNeeded()) {
            unlink($this->file);
        }
        
        $ms = $this->getMessage($level, $message, $context);
        
        $fos = new FileOutputStream($this->file, true);
        $fos->write($ms);
        $fos->flush();
        $fos->close();
    }
protected function logImpl($level, $message, array $context = array())
    {
        if (! $this->levelHasReached($level)) {
            return;
        }
        
        if ($this->isRotationNeeded()) {
            unlink($this->file);
        }
        
        $ms = $this->getMessage($level, $message, $context);
        
        $fos = new FileOutputStream($this->file, true);
        $fos->write($ms);
        $fos->flush();
        $fos->close();
    }
This function provides the real logging function.

First the log file size is checked.
When the maximum size has reached, the file will be overwritten.
Otherwise the log string is appended.

@param integer $level
The arbitrary level
@param string $message
The message to log
@param array $context
The context of logging