sort-pos-params   [plain text]

# Sort the positional paramters.
# Make sure the positional parameters are passed as arguments to the function.
# If -u is the first arg, remove duplicate array members.
sort_posparams()
{
	local -a R
	local u

	case "$1" in
	-u)	u=-u ; shift ;;
	esac

	# if you want the case of no positional parameters to return success,
	# remove the error message and return 0
	if [ $# -eq 0 ]; then
		echo "$FUNCNAME: argument expected" >&2
		return 1
	fi

	# make R a copy of the positional parameters
	R=( "${@}" )

	# sort R.
	R=( $( printf "%s\n" "${R[@]}" | sort $u) )

	printf "%s\n" "${R[@]}"
	return 0
}

# will print everything on separate lines
set -- 3 1 4 1 5 9 2 6 5 3 2
sort_posparams "$@"

# sets without preserving quoted parameters
set -- $( sort_posparams "$@" )
echo "$@"
echo $#

# sets preserving quoted parameters, beware pos params with embedded newlines
set -- 'a b' 'a c' 'x z'

oifs=$IFS
IFS=$'\n'
set -- $( sort_posparams "$@" )
IFS="$oifs"

echo "$@"
echo $#

sort_posparams