Information processing apparatus and non-transitory computer readable recording medium

A non-transitory computer readable recording medium that records an information processing program executable by an information processing apparatus selectively executable a normal mode or a sleep mode including

• a main system that operates in the normal mode, the main system including a memory and a processor, the memory storing an identifier list,
• a sub system that operates in the sleep mode, and
• a network interface that executes connectionless communication with an external device connected to a network,
• the information processing program causing the processor of the main system to operate as:
• a network interface controller module that
• reads an identifier described in a header of an application layer of a request frame received by the network interface, and registers the identifier in the identifier list, and
• reads the identifier described in a header of an application layer of a response frame to be sent by the network interface, and deletes the identifier from the identifier list;
• and
• an energy-saving controller module that
• determines whether or not an identifier remains in the identifier list when the information processing apparatus is about to shift from the normal mode to the sleep mode,
• if it is determined that an identifier remains, temporarily stops shifting from the normal mode to the sleep mode, and
• if it is determined that no identifier remains, shifts from the normal mode to the sleep mode.