use File::Temp 'tempfile';
my ($fh, $output) = tempfile();
close($fh);

open my $remote, "| ssh $user\@$hostname >$tempfile"
    or die "Couldn't launch ssh ssh $user\@$hostname: $!";
print $remote "some test command\n";
print $remote "another test command\n";
print $remote "quit\n";

open my $fh, '<', $tempfile
    or die "Couldn't read the tempfile?!";
while(<$fh>) {
    print "Remote: $_";
};