cat -- display directory

syntax:  cat [pathname] [-t] [-s] [-f filetype] [-a sort_keys] [-i]

ex:      cat
         cat -a
         cat /disk -it
         cat -fbas
         cat /mydisk -tfSYS
         cat .62 -s
         cat ?:dir

Displays the contents of the directory specified by pathname; wildcards are 
allowed.  (If no pathname is given, displays the contents of the current 
directory.)  The following options are available:

   -t: tree format--show contents of directories indented under the directory 
       names

   -i: show files and directories even if they are invisible (use the 'touch'
       command to make a file visible or invisible)

   -s: short form--display name and filetype only

   -f: show only files of given type (if -t is given, DIRs are also shown)

   -a: arrange--sort the listing according to the characters following '-a'.  
       If no characters follow, the listing is sorted alphabetically by 
       filename.  The following sorting keys may be combined by listing the 
       most significant keys first.  Capitalizing a letter reverses the order 
       of the sort on that key.

       n:  name (a to z)
       m:  modified date/time (newest to oldest)
       f:  filetype ($00 to $ff)
       t:  same as f
       s:  size in bytes (largest to smallest)
       x:  auxiliary type ($0000 to $ffff)
       b:  list files needing backup before files not needing backup

   Examples:

   cat -a
   cat -an
      arrange by name from a to z

   cat -aN
      arrange by name from z to a

   cat -afX
      arrange by increasing filetype and decreasing auxiliary type within
      each filetype

Note that '-t' is ignored when '-a' is used.