Configuration_File Issue with file_get_contents()

I needed to adjust he oauth_client.php file with my system, thought this might be a good update for all users:


if(!($json = @file_get_contents(__DIR__ .'/'. $this->configuration_file)))
{
if(!file_exists(__DIR__ .'/'. $this->configuration_file))
return $this->SetError('the OAuth server configuration file '.$this->configuration_file.' does not exist');
return $this->SetPHPError('could not read the OAuth server configuration file '.$this->configuration_file);
}

Is there a reason why you could not prepend __DIR__ .'/' to the value you set to the configuration_file variable?