Page of GC20-1821-3 As Updated April 1, 1981 by TNL GN25-0840 Documentation Only • updated references in
General Considerations" support for Multiple SRF VMDUMP command, and
Extended Control program
"Section 1.
to reflect
devices, the
the 3031AP
Support. • Incorporated technical and editorial
changes to appropriate sections.
Summary of Amendments
For GC20-1821-3
As Updated by GN25-0495 VM/370 Release 6 PLC 4
Summary of Amendments xi

Page of GC20-1821-3 As Updated April 1, 1981 by TNL GN25-0840 Summary of Amendments
For GC20-1821-3 VM/370 Release 6 PLC 1 Ne!: Proaram and Support VM/370 introduces a new DIAGNOSE instruction code X'84' which updates
statements in a directory entry "in
place"; that is, when the directory
entry size does not change, it updates
the entry without recompiling and
replacing the entire VM/370 system
directory entry file. This DIAGNOSE code has been added to the summary of
diagnose codes in "Section 1. General
Considerations." Pro"qram and Support VM/370 introduces a new DIAGNOSE instruction code X'74'. It has a
twofold purpose: (1) to load a specific 3800 named system into a virtual
machine, and (2) to save a storage image
in a specific 3800 named system. This DIAGNOSE code has been added to the
summary of diagnose codes in "Section 1.
General Considerations." proqram and Support VM/370 introduces a new DIAGNOSE instruction code X'78'. It permits
communication between a virtual machine
and VM/370 for MSS support. This DIAGNOSE code has been added to the
summary of diagnose codes in "Section 1.
General Considerations." VM/370 supports user minidisks on
mass storage system 3330V volumes. The
minidisks appear to the virtual machine
to be defined on a permanently mounted IBM 3330-1 disk drive. MSS volumes may also be dedicated and attached to a
virtual machine as either 3330V or devices. For more information,
refer to the topic "IBM 3850 Mass Storage System Considerations" in "Section 4. OS/VS in a Virtual Machine."
New: Program and Support VM/370 supports suppression of passwords
entered on the command line for the LOGON, AUTOLOG, and LINK commands. The
intent is to force passwords to be
masked for security purposes. These
commands reflect this support where
applicable in this publication. Documentation Only This reV1S10n entirely reorganizes the
contents of this publication. It also
incorporates minor, miscellaneous
technical and editorial changes to
several sections. The reorganization
provides information more conveniently
for its intended audience: System programmers who run System/360 or System/370 operating systems under the
control of VM/370, and VM/370 system
programmers who use VM/370 or these
operating systems under the control of VM/370. The publication provides a "General
Considerations" section that describes
common aspects of running operating
systems under VM/370. This section also
describes how to use VM/370 functions
more efficiently when running operating
systems under VM/370. The other
sections in this publication cover the
system planning and operating
considerations when running VM/370, DOS/VS, and as/vs under VM/370. xii IBM VM/370 Operating Systems in a Virtual Machine