$ uname -a
Linux ibm-laptop.diversityarrays.com 4.1.34-33-default #1 SMP PREEMPT Thu Oct 20 08:03:29 UTC 2016 (fe18aba) x86_64 x86_64 x86_64 GNU/Linux
$ perl -v | head -2 | tail -1
This is perl 5, version 18, subversion 2 (v5.18.2) built for x86_64-linux-thread-multi

##</code><code>##

$ date; perl -wMstrict -le '$a=time;$SIG{ALRM}=sub{$b=time};alarm 2;<>;print $b-$a'; date
Sat Jul 21 05:55:19 AEST 2018

Use of uninitialized value $b in subtraction (-) at -e line 1, <> line 1.
-1532116519
Sat Jul 21 05:55:20 AEST 2018
$ 

##</code><code>##

$ date; perl -wMstrict -le '$a=time;$SIG{ALRM}=sub{$b=time};alarm 2;<>;print $b-$a'; date
Sat Jul 21 05:56:58 AEST 2018

2
Sat Jul 21 05:57:05 AEST 2018
$ 

##</code><code>##

$ date; perl -wMstrict -le '$a=time;$SIG{ALRM}=sub{$b=time};alarm 2;<>;print $b-$a'; date
Sat Jul 21 05:59:28 AEST 2018
^C
$ 

##</code><code>##

$ date; perl -wMstrict -le '$a=time;$SIG{ALRM}=sub{$b=time};alarm 2;<>;print $b-$a'; date
Sat Jul 21 06:00:13 AEST 2018
^C
$