perl sleep test

output

$ time ./test.sh 

real    0m6.020s
user    0m0.004s
sys     0m0.008s

run_script.sh

#!/bin/sh
sleep 6

test.sh

#!/bin/sh
a=`./timeout.pl 2 ./run_script.sh`

timeout.pl

#!/usr/bin/perl
use strict;
use warnings;
my $PID=$$;
my $timeout=shift;
my @args=@ARGV;

my $pid = fork();
defined $pid or die "fork: $!";
$pid == 0 && exec(@args);

my $timed_out = 0;
$SIG{ALRM} = sub { $timed_out = 1; die; };
alarm $timeout;
eval { waitpid $pid, 0 };
alarm 0;
if ($timed_out) {
    print "Timed out!\n";
    kill 9, $pid;
    kill 9,$PID;
}
elsif ($@) {
    warn "error: $@\n";
}

changing kill 9, $pid; to kill 9, $PID; not helps