1. An image input-output apparatus comprising: reader means for reading an original on an original table; memory means capable of storing image information; communication means for communication with another information processing apparatus through a communication medium; print means for printing image data; and control means for selectively executing a copy mode operation for printing the image data, read by said reader means, by said print means, a print mode operation for printing the image data, stored in said memory means, by said print means, or a read mode operation for storing the image data, read by said reader means, in said memory means; wherein said control means is adapted, in said copy mode operation, to mutually synchronize the reading operation by said reader means with the printing operation by said print means thereby transmitting the image data read by said reader means directly to said print means, and, in said print mode operation or in said read mode operation, to make access to said memory means according to the operation of said print means or said reader means.