Layout is a form of the Layout Directive Family that
inserts data whenever its pattern is matched. It takes a third
optional parameter which determines if the pattern is replaced,
append, or prepend. If nothing is specified the replaced is assumed.
This directive was added in version 3.1.0.
Layout "<-- copyright -->" "Copyright Foobar, 2000" replace
Layout </BODY> /usr/local/apache/htdocs/footer.html append
Layout </BODY> /copyright.cgi prepend