#!/usr/bin/perl

use strict;
use warnings;

sub function {
    print "Hello, world\n";
}


my $kid;
my $pid = open ($kid, "-|");
die "Failed to fork: $!" unless defined $pid;

unless ($pid) { # Child.
    function;
    exit;
}

undef $/;
my $scalar = <$kid>;

print "Got: $scalar";
__END__
Got: Hello, world
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See also the perlipc manual page.