Shell Wrapper Script

#!/bin/sh
{

show_help() {
echo "Usage: ${name:-"${0##*"/"}"} [COMMAND]
Example description.

  -h, --help
        display this help and exit
      --version
        output version information and exit"
}

process() {
local "LC_ALL" "LANG" "IFS" "line"
LC_ALL=C
LANG=C
IFS=""
while read -r "line"; do
	case "${line}" in
		'example')
			continue
		;;
		"${name:-"${0##*"/"}"}: exit code: "[0-9]*)
			code="${line##*": "}"
			break
		;;
		*)
			echo "${line}"
			code=1			
		;;
	esac
done
}

main() {
local "name" "code" "version"
name="Example"
version="1.0.0"
case "${#},${1:-""},${2:-""}" in
	0,,)
		:
	;;
	"1,-,"|"1,--,"|"1,/dev/stdin,"|"1,--,")
		shift 1
	;;
	"2,--,-"|"2,--,/dev/stdin")
		shift 2
	;;
	"1,-h,"|"1,--h,"|"1,--help,"|"2,-h,--"|"2,--h,--"|"2,--help,--")
		show_help
		exit 0
	;;
	"1,--version,"|"2,--version,--")
		echo "${name:-"${0##*"/"}"} ${version:-"1.0.0"}"
		exit 0
	;;
	*,--,*)
		shift 1
	;;
	*,-*)
		show_help 1>&2
		exit 1
	;;
esac
case "${1:-""}" in
	"")
		process
	;;
	*)
		if type "${1}" >/dev/null 2>&1; then
			{ command -- "${@}"; echo "${name:-"${0##*"/"}"}: exit code: ${?:-"1"}"; } | process
		else
			echo "${name:-"${0##*"/"}"}: ${1}: command not found"
			code=127
		fi
	;;
esac
exit "${code:-"0"}"
}

echo() {
printf -- '%s\n' "${*}"
}

main "${@}"
exit 1
}