# alarm time might be one second less than you said.
is( $@, "ALARM!\n", 'alarm w/$SIG{ALRM} vs system()' );
-ok( abs($diff - 3) <= 1, ' right time' );
+{
+ local $TODO = "Why does system() block alarm() on $^O?"
+ if $^O eq 'VMS' || $^O eq'MacOS' || $^O eq 'dos';
+ ok( abs($diff - 3) <= 1, " right time (waited $diff secs for 3-sec alarm)" );
+}