Preface
Terminology
This publication describes how to debug VM/SP and how to modify, extend, or
implement Control Program (CP) and Conversational Monitor System (CMS) functions. This information is intended for system programmers, system analysts,
and programming personnel.
This publication consists of three parts and three appendixes. "Part 1. Control Program (CP)" contains an introductory and functional
description of CP as well as guidance in implementing some CP features. "Part 2. Conversational Monitor System (CMS)" contains an introductory and
functional description of CMS including how eMS handles interrupts and SVCs, structures its nucleus and its storage, and manages free storage. Information on
saving the CMS system and implementing the Batch Facility is also included. "Part 3. Debugging with VM/SP" discusses the CP and CMS debugging tools and
procedures to follow when debugging. This part is logically divided into three
sections. The first section, "Introduction to Debugging", tells you how to identify
a problem and lists guidelines to follow to find the cause. The second section
describes the CP debugging commands and utilities, debugging CP in a virtual
machine, the internal trace table, and restrictions. A detailed description of CP dump reading is also included. The third section, "Debugging with CMS", describes the CMS debugging commands and utilities, load maps, and restrictions
and tells you what fields to examine when reading a CMS dump. "Appendix A: System/370 Information" describes the System/370 extended PSW and extended control register usage. "Appendix B: VM Monitor Tape Format and Contents" describes the format and
contents of data records for classes and codes of MONITOR CALL. "Appendix C: CMS Macro Library" lists and describes the CMS macros applica­
ble to VM/SP. Some of the following convenience terms are used throughout this publication:
Throughout this publication, the term "VM/SP" refers to the VM/SP program
package when you use it in conjunction with VM/370 Release 6. The terms "CP" and "CMS" refer to the VM/370 components enhanced by the func­
tions included in the VM/SP package. Any reference to "RSCS," unless oth­
erwise noted, is to the RSCS Networking Program Product (5748-XPl). Any
reference to "IPCS," unless otherwise noted, is to the IPCS Extended Program
Product (5748-SAl).
When you install and use VM/SP in conjunction with the VM/SP Release 6 System Control Program (SCP), it becomes a functional operating system that
provides extended features to the Control Program (CP) and Conversational
Monitor System (CMS) components of VM/370 Release 6. VM/SP adds no
additional functions to the Remote Spooling Communications Subsystem (RSCS) and the Interactive Problem Control System (IPCS) components of VM/370. However, you can appreciably expand the capabilities of these Preface vii

components in a VM/SP system by installing the RSCS Networking program
product (5748-XPl) and the VM/IPCS Extension program product
(5748-SAl). Unless otherwise noted, the term VSE refers to the combination of the DOS/VSE system control program and the VSE/ Advanced Functions program
product. In certain cases, the term DOS is still used as a generic term. For
example, disk packs initialized for use with VSE or any predecessor DOS or DOS/VSE system may be referred to as DOS disks.
The DOS-like simulation environment provided under the CMS component of
the VM/System Product, continues to be referred to as CMS/DOS. Unless otherwise noted, the term "EXEC" refers to EXECs using the System
Product Interpreter, EXEC 2, or CMS EXEC languages. Unless otherwise noted, the term "System/370" applies to the 4300 and 303X processors.
The following terms in this publication refer to the indicated support devices: • "2305" refers to IBM 2305 Fixed Head Storage, Models 1 and 2. I. "3262" refers to the IBM 3262 Printer, Models 1, 5, and 11. • "3270" refers to a series of display devices, namely, the IBM 3275, 3276 (re­
ferred to as a Controller Display Station), 3277, 3278, and 3279 Display
Stations. A specific device type is used only when a distinction is required
between device types.
Information about display terminal usage also applies to the IBM 3138, 3148,
and 3158 Display Consoles when used in display mode, unless otherwise noted.
Any information pertaining to the IBM 3284 or 3286 Printer also pertains to
the IBM 3287, 3288, and 3289 printers, unless otherwise noted. • "3330" refers to the IBM 3330 Disk Storage, Models 1,2, or 11; the IBM
3333 Disk Storage and Control, Models 1 or 11; and the 3350 Direct Access
Storage operating in 3330 compatibility mode. "3340" refers to the IBM 3340 Direct Access Storage Facility and the 3344
Direct Access Storage. • "3350" refers to the IBM 3350 Direct Access Storage Device when used in
native mode. "3375" refers to the IBM 3375 Direct Access Device. • "3380" refers to the IBM 3380 Direct Access Storage. The Speed Matching
Buffer Feature (No. 6550) for the 3380 supports the use of extended
count-key-data channel programs. I. "3430" refers to the mM 3430 Magnetic Tape Subsystem. "370X" refers to IBM 3704 and 3705 Communications Controllers.
yili VM/SP System Programmer's Guide