This invention completes an authentication procedure early when it is ready to directly communicate with a printer, and serves as a user interface device of a direct print system. To this end, when a digital camera DSC is ready to directly communicate with a printer, and receives from the printer an inquiry about objects stored and held by the camera, it assigns an object which contains a word serving as authentication information of those stored and held in the DSC to a first handler (S52), assigns other objects (image data and the like) to subsequent handlers (S53), and sends that assignment result to the printer (S54).