path-duplicates.sh

#!/bin/sh

echo "run script with ./path-duplicates.sh | column -t | sort "

echo "-------------- paths"
echo "$PATH" | tr ':' '\n'
echo ""
echo "--------------"

# turn off filename globbing, and
# split strings in unquoted variables on colons
set -f
IFS=:

# set the positional parameters to the list of
# directories in the PATH variable
set -- $PATH

# turn on filename globbing again
# (leave IFS as is, it won't affect anything else here)
set +f

# loop over those directories and do the things
for dir; do
	for pathname in "$dir"/*; do
		[ -x "$pathname" ] && printf '%s\t%s\n' "$dir" "${pathname##*/}"
	done
done |
	awk -F '\t' '
{
        dir[$2] = ( dir[$2] == "" ? $1 : dir[$2] "\t" $1 )
        count[$2]++
}
END {
        for (util in dir)
                if (count[util] > 1)
                        printf "%s\t%s\n", util, dir[util]
}'