Perl File Test Operators Cheat Sheet by Hameed

-r	File is readable by effective uid/gid.
-w	File is writable by effective uid/gid.
-x	File is executable by effective uid/gid.
-o	File is owned by effective uid.
-R	File is readable by real uid/gid.
-W	File is writable by real uid/gid.
-X	File is executable by real uid/gid.
-O	File is owned by real uid.
-e	File exists.
-z	File has zero size (is empty).
-s	File has nonzero size (returns size in bytes).
-f	File is a plain file.
-d	File is a directory.
-l	File is a symbolic link (false if symlinks aren't supported by the file system).
-p	File is a named pipe (FIFO), or Filehandle is a pipe.
-S	File is a socket.
-b	File is a block special file.
-c	File is a character special file.
-t	Filehandle is opened to a tty.
-u	File has setuid bit set.
-g	File has setgid bit set.
-k	File has sticky bit set.
-T	File is an ASCII or UTF-8** text file (heuristic guess).
-B	File is a "­bin­ary­" file (opposite of -T).
-M	Script start time minus file modifi­cation time, in days.
-A	Same for access time.
-C	Same for inode change time (Unix, may differ for other platforms)