-open(IFCONFIG, 'ip address|') # show *all*, addresses w/o label
- or open(IFCONFIG, 'ifconfig -a|') # probably skips addresses w/o label
- or die "** Cannot run 'ifconfig' or 'ip address': $!\n";
+open(IFCONFIG, '-|', (grep { -x "$_/ip" } split /:/, $ENV{PATH}) ? 'ip address' : 'ifconfig -a')
+ or die "** Cannot run 'ip address' or 'ifconfig -a'\n";