popen is broken

[weltling]

======== /tmp/hhvm_chdir.php =======

<?php

$pwd = getcwd();
echo "in ".$pwd."\r\n";
chdir("/tmp/somedir");
echo "now in ".getcwd()."\r\n";

$r = popen("./bash_cmd", "r");
$s = fgets($r, 1024);
pclose($r);

var_dump($s);
?>

======== /tmp/somedir/bash_cmd =========

#!/bin/sh

echo $PWD

exit 0

=========== hhvm ================

hhvm hhvm_chdir.php
in /tmp
now in /tmp/somedir
sh: ./bash_cmd: No such file or directory
bool(false)

========== php ==================

php hhvm_chdir.php
in /tmp
now in /tmp/somedir
string(13) "/tmp/somedir
"

[paulbiss]

I think we just need to pass the optional cwd argument to the LightProcess here.