VIRTUAL COMPUTER

PURPOSE:To attain a prescribed control processing without changing a host software operated on a virtual computer. CONSTITUTION:A discriminating part 6 in an I/O emulate part 4 of an emulator which realizes the operation of a host software 3 operating on a virtual computer 2 discriminates whether or not an input event is a designated event by referring to the designated event preliminarily stored in a storage part 7, and the designated event is communicated from a communicating part 8 to the host software 3 when the input event is not the designated event. When the input event is the designated event, the designated event is not communicated to the host software, an I/O control processing corresponding to the designated event is operated by an I/O control processing part 9, and a command control processing is operated by a command control processing part 10. Then, the prescribed control processing, for example, an interruption/resumption control is operated.