This document describes optional extensions to the language described in the hosts_access(5) document. The extensions are enabled at program build time. For example, by editing the Makefile and turning on the PROCESS_OPTIONS compile-time option.
The extensible language uses the following format:
daemon_list : client_list : option : option ...
The first two fields are described in the hosts_access(5) manual page. The remainder of the rules is a list of zero or more options. Any ":" characters within options should be protected with a backslash.
An option is of the form "keyword" or "keyword value". Options are processed in the specified order. Some options are subjected to %<letter> substitutions. For the sake of backwards compatibility with earlier versions, an "=" is permitted between keyword and value.