This is like an extended help for httpd, which will display all the httpd.conf directives and the places where they are valid. For a specific directive, it tells all the possible values and where it can be used inside the httpd.conf. This can be very helpful, when you want to quickly know about a particular Apache directive.
# httpd –L HostnameLookups (core.c) “on” to enable, “off” to disable reverse DNS lookups, or “double” to enable double-reverse DNS lookups Allowed in *.conf anywhere ServerLimit (prefork.c) Maximum value of MaxClients for this run of Apache Allowed in *.conf only outside, or KeepAlive (http_core.c) Whether persistent connections should be On or Off Allowed in *.conf only outside , or LoadModule (mod_so.c) a module name and the name of a shared object file to load it from Allowed in *.conf only outside , or