TESTrun: Skip "igrp" on FreeBSD. [skip appveyor]

Author: infrastation

testprogs/TESTrun

@@ -40,6 +40,10 @@ sub ipv6_enabled {
 	return (defined $config{INET6} && $config{INET6}) ? 'IPv6 syntax enabled' : '';
 }
 
+sub is_freebsd {
+	return $^O eq 'freebsd' ? 'running on FreeBSD' : '';
+}
+
 my %valid_filters = (
 	empty => {
 		DLT => 'EN10MB',
@@ -2326,6 +2330,10 @@ my %valid_filters = (
 			EOF
 	}, # igmp
 	igrp => {
+		# "igrp" uses IPPROTO_IGRP, which FreeBSD defines differently
+		# from all other supported OSes.  Skip the test until it is
+		# clear how to resolve this discrepancy.
+		skip => is_freebsd,
 		DLT => 'EN10MB',
 		expr => 'igrp',
 		aliases => ['ip proto 9'],