#!/bin/bash

Version=2.03
Myname="${0##*/}"

:<<'DOC'
= paths - list the current PATH, MANPATH and INFOPATH, marking doubles

= Synopsis
paths [-c]	

== Options
-h,--help	print this help and exit
-H,--Help	print full documentation via less and exit
-V,--version	print version and exit
-c,--color	Colorize duplicates

= Description
paths displays the contents of |$PATH|, |$MANPATH| and |$INFOPATH|, listing each directory
on a separate line and marking duplicates.

For example:
   $ paths
   PATH:
     /home/wybo/bin
     /usr/local/texlive/2011/bin/i386-linux/
     /usr/local/sbin
     /usr/local/bin
     /usr/sbin
     /usr/bin
     /sbin
     /bin
     /usr/games
   MANPATH:
     ./man
     /usr/local/man
     /usr/local/texlive/2011/texmf/doc/man
   INFOPATH:
     /usr/local/texlive/2011/texmf/doc/info

Directories that occur more than once in the path will be marked with asterisks, for example:
   $ PATH=/local/bin:$PATH paths
   PATH:
   **/local/bin
     /home/wybo/bin
   **/local/bin
     /usr/local/texlive/2011/bin/i386-linux/
     /usr/local/sbin
     ...

With the |Red{-c}| option, ANSI coloring wil be used to mark doubles, instead of asterisks:
   $ PATH=/local/bin:$PATH paths
   PATH:
     Red{/local/bin}
     /home/wybo/bin
     Red{/local/bin}
     /usr/local/texlive/2011/bin/i386-linux/
     /usr/local/sbin
     ...

= Author
[Wybo Dekker](wybodekker@me.com)

= Copyright
Released under the [GNU General Public License](www.gnu.org/copyleft/gpl.html)
DOC


:<<'DOC' #----------------------------------------------------------------------
= handle_options
synopsis:	 handle_options "$@"
description:	handle the options.
globals used:	 Myname Version
globals  set:	 args
DOC
#-------------------------------------------------------------------------------
handle_options() {
   local options
   options=$(getopt \
      -n "$Myname" \
      -o hHIVc \
      -l help,Help,version,color -- "$@"
   ) || exit 1
   eval set -- "$options"
   color=false
   while [ $# -gt 0 ]; do
      case $1 in
      (-h|--help)    helpsrt
		     ;;
      (-H|--Help)    helpall
		     ;;
      (-V|--version) echo $Version
		     exit
		     ;;
      (-I)	     instscript "$0" ||
			die 'the -I option is for developers only'
		     exit
		     ;;
      (-c|--color)   color=true
		     shift
		     ;;
      (--)	     shift
		     break
		     ;;
      (*)	     break
		     ;;
      esac
   done
   args=( "$@" )
}

handle_options "$@"
set -- "${args[@]}"

for e in PATH MANPATH INFOPATH; do
   declare -A n
   echo $e:
   eval "e=\$$e"
   e=${e//::/:} # :: → :
   IFS=: entries=("$e")
   for p in ${entries[*]}; do 
      (( n[$p]++ ))
   done
   for p in ${entries[*]}; do
      if [[ ${n[$p]} -gt 1 ]]; then
         if $color; then
            echo "   $p"
         else
            echo '**' "$p"
         fi
      else
         echo '  ' "$p"
      fi
   done
done