mapfile.ksh

		function mapfile {
				typeset x IFS REPLY OPTARG OPTIND=1
				typeset -A ind opts=([c]=5000)
				integer ind o

				for x; do
					getopts :d:n:O:s:u:C:c:t x || break
					case $x in
						\?|:) return 1 ;;
						*) opts[$x]=$OPTARG ind[$x]=OPTIND
					esac
				done

				(( OPTIND > $# )) && set -- "$@" MAPFILE
				eval nameref ret=\$$OPTIND
				getAttrs -v x ret

				if [[ $x != *([ailux]) ]]; then
					printf '%s: %s: %s\n' "$FUNCNAME" "${!ret}" 'Type error.' >&2
					return 1
				fi

				[[ $x == *a* ]] || typeset -a ret
				(( o = (opts[O] - 1) ))
				IFS=

				while
					(( ++o ))
					${bool[${opts[s]+1-}1]+\:} let 'opts[s]--' || unset -v 'opts[s]'
					${bool[${opts[n]+1-}1]+\:} let 'opts[n]--' || break
					read -r ${opts[d]+'-d'} ${opts[d]+"${opts[d]}"} ${bool[${opts[s]+1-}1]+'ret[o]'}
				do [[ -v opts[t] ]] || ret[o]+=${opts[d]-$'\n'}
				done <&"${opts[u]:-0}"
				unset -v 'ret[o]'
		}