Transmitting device, receiving device, and the file transfer system

The present invention, in a file transfer system for transferring a file from the sending device to spontaneously receiving device, even if the file transfer is interrupted for a long time, for executing a process according to the file transfer efficiently transmitting device, it provides a receiving apparatus and a file transfer system. In the file transfer system of the present invention, the sink device is a receiving device receives from the source device is a transmitting device, and save the file data constituting the file, when interrogated a saved size from the source device, the saved size and it transmits to the source device. In addition, the source device, to detect the interruption of file transfer, after interrupting the file transfer has been detected, query the saved data size to the sink device. Furthermore, based on the saved data size sink device responds in accordance with the inquiry, and transmits the remaining file data constituting the file.