Apache Reference: mod_log_config, LogFormat
LogFormat
Define a Customized Log File Format
Syntax: LogFormat format [nickname]
Example: LogFormat "%h %l %u %t \"%r\" %s %b" clf
Since: Apache 1.0
This directive sets the format of the default log file set by the TransferLog directive or defines a customized format that is available under nickname to the CustomLog directive.