use strict ;
use warnings ;

alarm 2 ;
$SIG{ALRM} = sub{
	syswrite STDOUT, "s Timeout reached " ;
	print STDOUT "p Timeout reached " ;
} ; 
sleep(4) ;
syswrite STDOUT, "s Program end " ;
print STDOUT "p Program end " ;
sleep(2) ;
__END__
C:\perlproject>perl sigtst.pl
s Timeout reached s Program end p Timeout reached p Program end

s Timeout reached - Printed after 2 seconds
s Program end     - Printed after 4 seconds
p Timeout reached - Printed after 6 seconds
p Program end     - Printed after 6 seconds