This is a example of how run a command using as output the TTY, just like crontab -e or git commit does.
<?php
$descriptors = array(
array('file', '/dev/tty', 'r'),
array('file', '/dev/tty', 'w'),
array('file', '/dev/tty', 'w')
);
$process = proc_open('vim', $descriptors, $pipes);