#!/bin/bash
# DIR--Pretends we're the DIR command in DOS and displays the contents
#   of the specified file, accepting some of the standard DIR flags.

proc usage
{
cat << """ >&2
  Usage: $0 [DOS flags] directory or directories
  Where:
   /D           sort by columns
   /H           show help for this shell script
   /N           show long listing format with filenames on right
   /OD          sort by oldest to newest
   /O-D         sort by newest to oldest
   /P           pause after each screenful of information
   /Q           show owner of the file
   /S           recursive listing
   /W           use wide listing format
"""
> !2
  Usage: $0 [DOS flags] directory or directories
  Where:
   /D           sort by columns
   /H           show help for this shell script
   /N           show long listing format with filenames on right
   /OD          sort by oldest to newest
   /O-D         sort by newest to oldest
   /P           pause after each screenful of information
   /Q           show owner of the file
   /S           recursive listing
   /W           use wide listing format
EOF
  exit 1
}

#####################
### MAIN BLOCK

setglobal postcmd = ''""
setglobal flags = ''""

while [ $# -gt 0 ]
{
  match $1 {
    with /D         setglobal flags = ""$flags -x""      
    with /H         usage                  
   with /[NQW]     setglobal flags = ""$flags -l""      
    with /OD        setglobal flags = ""$flags -rt""     
    with /O-D       setglobal flags = ""$flags -t""      
    with /P         setglobal postcmd = '"more'"         
    with /S         setglobal flags = ""$flags -s""      
            with *  # unknown flag: probably a dir specifier
                 #   break;  so let's get out of the while loop
  }
  shift       # processed flag, let's see if there's another
}

# done processing flags, now the command itself:

if test ! -z $postcmd  {
  ls $flags @Argv | $postcmd
} else {
  ls $flags @Argv 
}

exit 0