Purpose of this information: APPC/MVS is an implementation of IBM's Advanced Program-to-Program Communication (APPC) in the MVS operating system. APPC/MVS allows MVS application programs to communicate on a peer-to-peer basis with other application programs on the same z/OS system, different z/OS systems, or different operating systems (including Microsoft Windows®, Sun Solaris, AIX, OS/400, OS/2, and VM in an SNA network. These communicating programs, known as transaction programs (TPs) and servers, together form cooperative processing applications that can exploit the strengths of different computer architectures. This book tells how to design and write APPC servers to run on MVS. A companion book, z/OS MVS Programming: Writing Transaction Programs for APPC/MVS, tells how to design and write APPC/MVS transaction programs.

In this book, the term APPC/MVS transaction program refers to a program, running in an MVS address space, that uses APPC/MVS services. The term transaction is not restricted to programs scheduled by the APPC/MVS transaction scheduler, or to programs using APPC/MVS services.

In this book, the term APPC/MVS server refers to a specific type of transaction program; one that can manage multiple inbound LU 6.2 conversations from multiple client transaction programs, serially or concurrently. The client programs may be running on the same system or on other systems in the SNA network (such as an OS/2 system running on a workstation).

Note that APPC/MVS transaction programs and servers are parts of cooperative processing applications and are distinct from, but coexistent and compatible with, CICS and IMS transaction processing applications.

This book is a companion to z/OS MVS Programming: Writing Transaction Programs for APPC/MVS, which describes callable services that are available to both APPC/MVS transaction programs and servers. This book describes the callable services that are useful only to APPC/MVS servers. Servers use these services to establish and manage one or more queues of inbound allocate requests from the installation's transaction programs. These queues are referred to as allocate queues. The services used to create and manage allocate queues are known as allocate queue services.

Who should read this information: This book is written for application programmers who use APPC/MVS application programming interfaces (APIs) to design and code applications. The book assumes the user understands the basic concepts of APPC/MVS, and can code in one or more high-level languages (HLLs) that support APPC/MVS servers. For a list of the HLLs that can be used to code APPC/MVS servers, see Table 1.

How to use this information: This information is from the set of programming books for MVS. It describes how to write programs in assembler language or high-level languages, such as C, FORTRAN, and COBOL. For more information about the content of this set of books, see z/OS Information Roadmap.

Where to find more information: Where necessary, this book references information in other books, using the shortened version of the book title. For complete titles and order numbers of the books for all products that are part of z/OS, see z/OS Information Roadmap. The following table lists the titles and order numbers of books for other IBM products.