| 摘要 |
PROBLEM TO BE SOLVED: To notify information indicating that a file is stored even if, for example, connection to a sender of the file is disabled and the file is received again.SOLUTION: If a file and file information and an identifier related to the file are received and it is determined that the file is not stored on the basis of file information, the file, the file information, and the identifier are stored while being linked to one another. If it is determined that the file is stored on the basis of the file information and it is determined that a stored identifier is identical to the newly received identifier, information indicating that the received file is stored is notified. |
