This is a description of a protocol, not the documentaion of some specific type of object that we have implemented. The COMMQ key {(commq)} obeys this protocol -- others may as well. A CPGCOMM key is kept by the VMGROUP object to be used when some signal is to sent to "your machine". This key is provided by the producer of a virtual machine, such as provided by (vmcommf), or by another system designed to play the role of a VM.

CPGCOMM(msg{=0},(8,tod),(8,sender),message==>c) Message for your VM

tod - Time message was sent

sender - The username of the sender

message - Text of message in EBCDIC

This operation returns when the CP simulator is able to receive another message.

Return codes:

0 - done

?? - Message cannot be accepted because a previous message is still being processed.

CPGCOMM(connection_waiting{=2}==>) There are one or more pending IUCV connections.

CPGCOMM(accepted{=3}, (2,pathid),(2,msglim),(1,flags), (16,userdata) ==>) IUCV Connection Complete

msglim - Maximum number of outstanding messages on the path (1-255).

Flags are:

X'20' - the VM may receive priority messages

X'40' - the path is initially quiesced.

X'80' - the connecting virtual machine can handle message data in the parameter list.

pathid - The pathid used with the "IUCV Connect" operation on the VMCOMM key.

Userdata - passed as part of the accept operation.

N.B. The associated IUCVPATH key is destroyed.

pathid - The pathid used with the "IUCV Connect" operation on the VMCOMM key or the "IUCV Accept" operation on the IUCVPATH key.

Userdata - passed as part of the sever operation.

pathid - The pathid used with the "IUCV Connect" operation on the VMCOMM key or the "IUCV Accept" operation on the IUCVPATH key.

Userdata - passed as part of the quiesce operation.

pathid - The pathid used with the "IUCV Connect" operation on the VMCOMM key or the "IUCV Accept" operation on the IUCVPATH key.

Userdata - passed as part of the resume operation.

tag - from the "Send" operation.

pathid - The pathid used with the "IUCV Connect" operation on the VMCOMM key or the "IUCV Accept" operation on the IUCVPATH key.

Flags are:

X'20' - This is a priority reply

X'80' - Message data is included in the parameter string. The msglength is 8.

Other bits are zero.

msgid - The ID number of this message

audit - The IUCV audit trail for this message, left justified.

count - Residual count in buffer or of un-received message.

data - Used only if (flags & X'80'). Contains the reply.

pathid(x2) - The pathid used with the "IUCV Connect" operation on the VMCOMM key or the "IUCV Accept" operation on the IUCVPATH key.

Flags(x1) are:

X'10' - One way message, No reply expected

X'20' - This is a priority message

X'80' -

If one, message data is included in the parameter string. The data is in the 8-byte field consisting of the data1 and msglength fields.

If zero, message data is not included in the parameter string. Msglength has the length of the message, and data1 is not used.

Other bits are zero.

msgid(i4) - The ID number of this message

targetclass(x4) - value passed by sender. Can be used for message selection

data1(x4) - Used only if (flags & X'80'). Contains part of the message.

msglength(i4) - Length of message to be sent.

maxreplylen(i4) - Maximum length of the expected reply.

{ni}CPGCOMM(vmcf_interrupt{=10}, (40,VMCF-external-interrupt-header) ==>)

VMCF-external-interrupt-header - As described by IBM with the additional type of X'FFFF' indicating an identify response message {see (vmcomm)}.

sender - The username of the sender

message - Text of message in EBCDIC

This operation returns when the CP simulator is able to receive another special message.

Return codes:

0 - done

?? - Message cannot be accepted because a previous message is still being processed.