Special Message Facility The special message facility is a method of transferring special
messages from a user to a specially programmed receiving virtual machine
for processing. The sender of the message need cnly issue the new CP command, SMSG, rather than having to establish authorization with the
receiving virtual machine. CP, through its message and Virtual Bachine Communication Facility (YMCF) modules, acts as a virtual machine on behalf of the issuer of the SKSG command. The receiving virtual machine must issue an AUTHORIZE and
set on the SMSG flag if it wishes to receive special messages. The SMSG flag is set on by issuing the SET SMSG co.mand or ty setting the flag in
the yMCl parameter list when issuing the lUTHORIZI control subfunction (DIAGNOSE X'68'). The receiving virtual machine is also responsitle for accepting and
processing the special message that is defined in form and content hy the installation. For example, the receiving virtual machine might be
programmed to accept only messages containing commands to process user
files being sent to remote locations. Existing means and paths of
com.unication and data transfer remain intact. The user still has the CP command, MESSAGE, available to him and he can still exchange data
with other virtual machines via mutual authorization.
In addition to the SMSG co.mand, two other CP co.mands have been
modified to reflect support of this facility. The SftSG operand has been
added to the SET command to indicate if the receiving virtual machine is
to receive special messages. The QUERY SET co.mand is now modified to
include a response indicating the special message status, either ON or OFF. SRL AND PROGRAM LOGIC PUBLICATIONS The following publications contain information on the special message
facility: GC20-1800 Intrcduction GC20-1801 Planning and system Generation Guide GC20-1807 System Programmer's Guide GC20-1808 System Messages GC20-1818 CftS Command and Macro Reference GC20-1819 CftS User's Guide GC20-1820 CP Command Reference for General Users SY20-0884 Data Areas and Control Block Logic SY20-0886 System Logic and Problem Determination Guide, Vol. 1
1-22 IBM VM/370 Release 6 Guide

Modification to the DIAGNOSE X'8' Interface
The CP DIAGNOSE X'8' instruction has been .odified to allow any user to
receive his DIAGNOSE X'8' response in a user specified virtual storage location. The response to any CP ccm=and is now availatle in machine readable form in the user's virtual storage at the completion of the
co.mand. The interface which allows a user to receive DIAGNOSE X'8' responses at his console remains intact. SRL AND PROGRAM LOGIC PUBLICATIONS The following publications contain information on the modification to
the DIAGNOSE X'8' interface: GC20-1807 System programmer's Guide 5Y20-0886 System Logic and Problem Determination Guide. Vol. 1 Section 1: Summary of Changes to the VM/370 systea 1-23