Perl pragma to control the filetest permission operators
Description
The default behavior of file test operators (e.g. "-r") is to use the simple
mode bits as returned by the stat() family of system calls. However, many
operating systems have additional features to define more complex access
rights, for example ACLs (Access Control Lists). For such environments, "use
filetest" may help the permission operators to return results more consistent
with other tools.