KNAME=$(uname -s)
	ARCH=$(uname -m)
	case "${KNAME}" in
	SunOS)
		ARCH=$(isainfo -k)
		;;
	esac
}

## FIXME:
## In OSX, 'readlink -f' option does not exist, hence
## we have our own readlink -f behavior here.
## Once OSX has the option, below function is good enough.
##
## readlink() {
##     return /bin/readlink -f "$1"
## }
##
readlink() {
	TARGET_FILE=$1

	cd $(dirname $TARGET_FILE)

// in http://docs.aws.amazon.com/general/latest/gr/sigv4-create-canonical-request.html
func signV4TrimAll(input string) string {
	// Compress adjacent spaces (a space is determined by
	// unicode.IsSpace() internally here) to one space and return
	return strings.Join(strings.Fields(input), " ")
}

// checkMetaHeaders will check if the metadata from header/url is the same with the one from signed headers