(PHP 5 >= 5.1.2)
lchgrp — Changes group ownership of symlink
Attempts to change the group of the symlink filename to group .
Only the superuser may change the group of a symlink arbitrarily; other users may change the group of a symlink to any group of which that user is a member.
Path to the symlink.
The group specified by name or number.
如果成功则返回 TRUE，失败则返回 FALSE。