i tried to use the AlarmCall but failed.
even i cant succeed run the given example in the module:

use Sys::AlarmCall;
alarm_call(4, 'read', STDIN, $r, 5);
print $r;

if i never key in anything, the stuff would block, wont timeout after 4 seconds as i assume.
and it would just end the program if i enter some text and printout the input..
what's wrong hunh??