1. An image input/output apparatus comprising: an input unit for performing at least one of a plurality of input processes, wherein said plurality of input processes include a process of inputting a set of document data from a document scanner unit and a process of inputting a set of document data from an external apparatus; an output unit for performing at least one of a plurality of output processes, wherein said plurality of output processes include a printing process of printing the set of document data input by the input unit, a storage process of storing the set of document data into an image storage unit and a transmission process of transmitting the set of document data to another apparatus; a setting unit for setting at least one of a plurality of processing conditions, wherein said plurality of processing conditions include a processing condition associated with a scan-all-first mode in which a plurality of sets of document data input separately by the input unit are allowed to be processed as a single group of data in the at least one of said plurality of output processes performed by the output unit; and a control unit for performing controls, wherein if an inputting process of said set of document data in the scan-all-first mode is started without said setting unit setting a processing condition for said document data to be processed in the scan-all-first mode, one or more of said plurality of processing conditions is allowed to be set after the start of the input process of said set of document data by the input unit in the scan-all-first mode.