Paqe of GC20-1807-7 As Updated April 1, 1981 by TNL GN25-0829 V*2 (VMCMEFLG) VM CMFUNC VMCMMID VMCMUSER VMCMVADA VMCMLENA VMCMVADB VMCMLENB VMCMUSE VMCMBUF Contains a data transfer error code indicating success or
errors associated with a data transfer operation. (Refer
to the section "Data Transfer Error Codes. ") contains the subfunction code of the original request.
The sink virtual machine will use this field to determine
the type of request. The possible subfunction codes are: VMCPSEND VMCPSENR VMCPSENX VMCPIDEN X' 000 2' -SEND X'0003' - SEND/RECV X'0004' - SENDX X'OOOA' - IDENTIFY contains the message ID associated with the original
source request.
contains the userid of the source virtual machine for SEND
external interrupts and the userid of the sink virtual
machine for RESPONSE external interrupts. If a SMSG command was issued, 'SYSTEM' appears in this field.
Contains the address of the original SEND data for SEND
requests. This field would normally have no meaning to
the sink virtual machine.
Indicates the length of SEND data for
interrupts. It indicates a data transfer
for RESPONSE external interrUpts. SEND externa I residual count
Contains the virtual address of the REPLY buffer for SEND/RECV requests. This field has no meaning to the sink
virtual machine.
contains the length of the source virtual machine REPLY buffer for SEND/RECV external interrupts; contains the
residual REPLY count for RESPONSE external interrupts.
The sink virtual machine uses this field to determine the
maximum length of the REPLY; the source virtual machine
uses this field to determine the length of the sink
virtual machine REPLY data.
contains the
sink virtual
the source
interrupts.
contains the
command.
user doubleword, which is transmitted to the
machine with SEND external interrupts and to
virtual machine with RESPONSE external
If a SMSG command was issued, this field
user doubleword of the issuer of that
This is the optional data buffer used by the SENDX subfunction. The data sent with the SENDX subfunction is
moved into this buffer. The buffer size is specified when
a virtual machine executes the VMCF AUTHORIZE subfunction. VMCF USER DOUBLEWORD VMCF a doubleword for user data that can be transmitted within
the external interrupt message header. A user supplies the doubleword
of data within the parameter list (VMCPARM) for certain VMCF request
(that is, SEND, SENDX, SEND/RECV, RECEIVE, REPLY, IDENTIFY, and REJECT). You can use the user doubleword in any manner you desire. The
doubleword is transmitted within the external interrupt message header
for both SEND and RESPONSE type external interrupts.
166 IBM VM/370 System Programmer's Guide

Page of GC20-1807-7 As Updated April 1, 1981 by TNL GN25-0829
The user doubleword can be used for control information in a
user-defined higher level protocol. That is, you could have your own
message headers defined within the data transmitted from one virtual
machine to another. The user doubleword could be used to control such a I-'.L. V\..V\...VJ.. Part 2. Control Proqram (CP) 166. 1