#!/usr/bin/perl

use strict;
use warnings;
use threads;

my $t1 = async { qx(perl process1); }
my $t2 = async { qx(perl process2); }

my @out1 = $t1->join;
my @out2 = $t2->join;

print "t1: @out1\n";
print "t2: @out2\n";