共通プログラミング インターフェイス通信(A set of C-language routines that applications distributed across an SNA network can use to work together. Through the Common Programming Interface for Communications (CPI-C), distributed applications on computers communicating as peers can exchange data to accomplish a processing task, such as querying a remote database or copying a remote file. Specifically, CPI-C provides access to interprogram services such as sending and receiving data, synchronizing processing between programs, and notifying a partner of errors in the communication)