# File lib/RMagick.rb, line 1522
    def ping(*files, &block)
        if (files.length == 0)
            raise ArgumentError, "no files given"
        end
        files.each { |f|
            Magick::Image.ping(f, &block).each { |n| self << n }
            }
        @scene = length - 1
        self
    end