sub gen2nfs_sub_ifconfig_ipv4 {

                my $ethif = shift;
                my $ifconfig = "$IFCONFIG";
                my $string = 'inet\saddr:';
                local *IFCONFIG;

                open (IFCONFIG, "$ifconfig $ethif 2>&1 |") || die ("ERROR:1 (gen2nfs_sub_ifconfig_ipv4): $! $_");

                while(<IFCONFIG>) {

                        # search IP 123.123.123.123
                        #           ddd.ddd.ddd.ddd
                        # \d = digit
                        # {1,3} 1,2 or 3 digits

                        if ( /.*$string(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})/ ) {
                                return "$1";
                                last;
                        };
                }

                close (IFCONFIG);
}