+PH/05 There is now a new ${if condition called "match_ip". It is similar to
+ match_domain, etc. It must be followed by two argument strings. The first
+ (after expansion) must be an IP address or an empty string. The second
+ (after expansion) is a restricted host list that can match only an IP
+ address, not a host name. For example:
+
+ ${if match_ip{$sender_host_address}{1.2.3.4:5.6.7.8}{...}{...}}
+
+ The specific types of host list item that are permitted in the list are
+ shown below. Consult the manual section on host lists for further
+ details.
+
+ . An IP address, optionally with a CIDR mask.
+
+ . A single asterisk matches any IP address.
+
+ . An empty item matches only if the IP address is empty. This could be
+ useful for testing for a locally submitted message or one from specific
+ hosts in a single test such as
+
+ ${if match_ip{$sender_host_address}{:4.3.2.1:...}{...}{...}}
+
+ where the first item in the list is the empty string.
+
+ . The item @[] matches any of the local host's interface addresses.
+
+ . Lookups are assumed to be "net-" style lookups, even if "net-" is not
+ specified. Thus, the following are equivalent:
+
+ ${if match_ip{$sender_host_address}{lsearch;/some/file}...
+ ${if match_ip{$sender_host_address}{net-lsearch;/some/file}...
+
+ You do need to specify the "net-" prefix if you want to specify a
+ specific address mask, for example, by using "net24-".
+