ルートディレクトリ方向に向かってファイルを検索するコマンド

findr.sh

#!/bin/bash

usage_exit() {
	local PROG=$(basename "$0")
	cat <<EOS >&2
$PROG -- find a file towards the root directory

$PROG [OPTIONS] FILENAME

OPTIONS
    -d  show only a directory name
    -h  show this help
EOS
	exit 1
}

ONLY_DIRNAME=false
case "$1" in
	-h | --h | "")
		usage_exit
		;;
	-d)
		ONLY_DIRNAME=true
		shift
		;;
esac

FILENAME="$1"
dir=$(pwd)
while :; do
	f="$dir/$FILENAME"

	if [[ -f "$f" ]]; then
		if "$ONLY_DIRNAME"; then
			echo "$(dirname "$f")"
		else
			echo "$f"
		fi
		exit 0
	fi

	if [[ "$dir" == "/" ]]; then
		exit 1
	fi

	dir=$(dirname "$dir")
done