A collection of system calls, kernel resources, and kernel utility routines that can create, use, and dismantle a streAM. A "streAM head" provides the interface between the streAM and the user processes. Its principal function is to process STREAMS-related user system calls. A "streAM module" processes data that travel bewteen the streAM head and driver. The "streAM end" provides the services of an external input/output device or an internal software driver. The internal software driver is commonly called a pseudo-device driver. The STREAMS concept has been formalised in UnixSystem V. For exAMple, SVR4 implements sockets and pipes using STREAMS, resulting in pipe(2) openning bidirectional pipes. [IBM AIX 3.2 Communication ProgrAMming Concepts, SC23-2206-03]. (1999-06-29)