HHVM和PHP exec（）

Question

I'm trying to use the exec() PHP function on a system that run on HHVM.

Unfortunately, the command (even a simple echo) return an empty string, without any error. When I try the command inside terminal as root the output is correct.

PHP Safe mode is off, I guess this is a permission issue but I don't know how to solve it.

Answer 1

我已经将HHVM更新为3.x，它现在正像一种魅力一样工作。