This is a aajor revision of, and obsoletes. 5120-0884-2 and Technical
Bewsletters 5B25-0413, 5125-0453, and 5125-0466. This edition applies
to § 1 (Prograa Level Change) of the IE! Virtual !achine Facility/370, and to all subsequent releases unless otherwise indicated
in new editions or Technical Bewsletters. Technical changes and additions to text and illustrations are indicated by a vertical bar to the left of the change. Changes are periodically aade to the inforaation herein; before using
this publication in connection with the operation of IB! systeas,
consult the latest Order Ro. GC20-0001, for
the editions that are aFplicable and current.
Publications are not stocked at the address given below; requests for
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the infor.ation you supply. © copyright International Business !achines corporation 1916, 1977,
1979

This publication contains descriptions of major data areas and control blocks used by the three major components of V"/370. The
three cOllponents are: I • The Control Prograll (CP) I • The Conversational Monitor System (CMS) I • The Remote Spooling I Subsystem (RSCS) Comllunications There are three sections
appendixes, as follows:
and five • "Section 1. CP Data Areas and Control Blocks" contains information about CP data areas and control blocks. • "Section 2. CMS Data Areas and Control BloCKS" contains information on CMS data
areas and control blocks. • "Section 3. RSCS Data Areas and Control Blocks" contains information on RSCS data areas and control blocks. • "Appendix A. CP and RSCS Equate Symbols" contains assembler language equate symbols used by CP and RSCS to reference
data. • "Appendix B. RSCS Control Areas"
contains RSCS control areas that define
constants and variables used during execution. • "Appendix C. RSCS Request Elements"
contains RSCS request eleaents that are
the tables used by RSCS for task-to-task
communication. • "Appendix D. CMS Equate
contains CMS equate symbols. Symbols" • "Appendix E. Data Areas and Control Block References" contains information
on the modules that reference data areas
and control blocks. OTHER VM/370 DATA AREAS AND CONTROL BLOCKS Some data areas and control blocks that
affect VM/370 service and support programs are not included in this publication.
Information on these data areas and control
blocks can be found in the ViItua! Preface Facil!llL37.Q: Service Routi!!es 19qic, Order No. SY20-0882. RELATEr PUBLICATIONS This putlication
conjunction with:
should be used 1 Control Pr.Q.9!U (Q), Order No. 5Y20-0886 in l Conversatienal MCni!.Q£ Order No. Sy20-0887 Guide, Order No. GC20-i807 -
For information on how to use the fourth
component interactive problem centrol system -- and its facilities, the hardware
and software support perscnnel or the
installation system programmer should use: IEM Virtual Machine Facility/370: system Guide, Order No. GC20-1823,. This publication addresses and describes
the major control blocks associated with CP, CMS, and RSCS. Generally, data areas,
or scratch areas that are created and exist
only during the execution ef a particular module are not described in this
publication. In this publication, the data
areas and control blocks are arranged in
alphabetical order by DSECT name.
The CMS and RSCS cOllponents operate
under control of CP. Each component
creates, updates, and erases its own
control blocks and data areas.
Preface iii