P934A1N2 says to Ubuntu 台灣社群
> PRoot is program that implements functionality similar to GNU/Linux's chroot, mount --bind, and binfmt_misc in user-space, allowing an unprivileged user to execute programs with an alternative root directory, much like a chroot "jail". This is useful in cases where a chroot is not possible due to a lack of root privileges. 一句話解釋:就是使用者空間的 chroot 更簡單:免 root 的 chroot