'Translate conf_file to a corresponding pid_file
:param conf_file: an conf_file for this server, a string
:returns: the pid_file for this conf_file'

def get_pid_file_name(self, conf_file):

    return conf_file.replace(os.path.normpath(SWIFT_DIR), self.run_dir, 1).replace(('%s-server' % self.type), self.server, 1).replace('.conf', '.pid', 1)
