dir

#!/bin/sh
# dir (Bourne shell script) -- long-lists a directory using less
# Pipes the output of ls -la[g]F through an awk script that puts the
# directories first.  If the output consists of a single line detailing a file
# which is a symbolic link, dir automatically runs itself again, following the
# link.  (By adding the -L argument to the ls command.)

# The awk program causes awk to exit with 

if [ "x$1" = "x-A" ] ; then
  all_switch=A
  shift
else
  all_switch=a
fi

ls -l${all_switch}F`if [ -n "${SYSV-berk}" ] ; then echo g ; fi` "$@" |
awk 'BEGIN  {
	       attrfield = 1
            }

     /^$/   {
              for (counter = 0; counter < num_lines; ++counter)
                print( lines[counter] )
              num_lines = 0
              entry_num = 0
              print
              ++subdir_number
              next
            }

     {
       if (subdir_number == 0)
         {
           if (entry_num == 0 && $1 == "total" && $0 !~ /:$/)
	     one_dir_listing = 1

	   if (entry_num <= 2 && $1 + 0 != 0)
	     attrfield = 2
         }

       if (entry_num == 0 && $0 ~ /:$/ || \
	   $1 == "total" && $0 !~ /:$/ || \
           $(attrfield) ~ /^d/ || $(attrfield) ~ /^l/ && $0 ~ /\/$/)
         print
       else
         lines[num_lines++] = $0
       ++entry_num
     }

     END    {
              for (counter = 0; counter < num_lines; ++counter)
                print( lines[counter] )
              if (one_dir_listing == 1) 
                exit( 128 )
            }' > /tmp/tmp.$$

awk_status=$?

if [ $awk_status = 0 -o $awk_status -ge 128 ] ; then
  # If standard output is a terminal, then the listing will be shown using the
  # PAGER program, otherwise it will be sent to standard output:
  if [ ! -t ] || [ -z "$PAGER" ] ; then
    cat /tmp/tmp.$$
  elif [ "$PAGER" = less ] ; then
  ##     # Find out how many non-option parameters there are (argc - index + 1):
  ##     echo 'set index = 1
  ##     while (index <= $#argv && `echo x$(index) | cut -c2` == "-")
  ##       @ index++
  ##     end'
  ##     if ($#argv > $index) then
  ##       set prompt_option = '-PMListing of current directory, line %lt/%L %pt'
  ##     else if ($#argv == $index) then
  ##       set prompt_option = '-PMListing of ${$index}, line %lt/%L %pt'
  ##     else
  ##       set prompt_option = '-PMMulti-file listing, line %lt/%L %pt'
  ##     endif
  ##   else
  ##     set prompt_option
  ##   endif
    eval last_arg=\$$#
    if [ $awk_status = 128 -a $# -gt 0 -a "x`echo $last_arg | cut -c1`" != x- ] ; then
      less_prompt_info="Listing of $last_arg"
    else
      less_prompt_info="Directory listing"
    fi
    less -EX -PM"$less_prompt_info, line %lt/%L %pt\%" /tmp/tmp.$$ 
  else
     $PAGER /tmp/tmp.$$ 
  fi
  
  if [ $# -eq 0 -o "x$1" != "x-L" ] ; then
    wc_output=`wc /tmp/tmp.$$`
    if [ `echo $wc_output | sed -e 's/ .*//'` = 1 ] ; then
      if [ -n "`sed -n -e '/^[ 0-9]*l/p' /tmp/tmp.$$`" ] ; then
          link_target=`sed -e 's/.*-> \(.*\)/\1/' /tmp/tmp.$$`
          echo "$link_target:"
          exec $0 -L "$@"
      fi
    fi
  fi
fi
  
rm /tmp/tmp.$$