Output message from message exit to client

Depending on the type of IMS Connect client and the user message exit used to support the client, the format of the message structure differs.

This topic contains Product-sensitive Programming Interface information.

The output message from the message exit that is sent to IMS Connect client applications is in one of the following formats:

IMS TM Resource Adapter message structure

The following table shows the message format of the output message from the user message exit HWSJAVA0. The table provides information about the length and meaning of the fields in the output message.

Table 1. Output message format from the user message exit HWSJAVA0
Field Length Meaning
LLLL 4 bytes Total message length
Id 8 bytes *HWSJAV*
OTMA HDRs 466 - 970 bytes Mapped by the HWSOMPFX macro in the IMS.SDFSMAC data set. For a description of the fields see OTMA header fields used by IMS Connect. If the security section of the OTMA header contains network security information, the size of the header can be up to 504 bytes larger than without the information.
Control data (applicable to synchronous callout request) n bytes Control data sent by the IMS application program
LL 2 bytes Length of data segment
zz 2 bytes Reserved (set to binary zeros)
DATA n bytes User data
OTMA CTL HDR 32 bytes Mapped by the HWSOMPFX macro in the IMS.SDFSMAC data set. For a description of the fields see OTMA header fields used by IMS Connect.
LL 2 bytes Length of this data segment
zz 2 bytes Reserved (set to binary zeros)
DATA n bytes User data
...    
OTMA CTL HDR 32 bytes Mapped by the HWSOMPFX macro in the IMS.SDFSMAC data set. For a description of the fields see OTMA header fields used by IMS Connect.
LL 2 bytes Length of this segment
zz 2 bytes Reserved (set to binary zeros)
DATA n bytes User data
OTMA CTL HDR 32 bytes Mapped by the HWSOMPFX macro in the IMS.SDFSMAC data set. For a description of the fields see OTMA header fields used by IMS Connect.
LL 2 bytes Length of data segment
zz 2 bytes Reserved (set to binary zeros)
DATA n bytes User data
...    
LL 2 bytes Length of this data segment
zz 2 bytes Reserved (set to binary zeros)
DATA n bytes User data

User-written application message structure

The user-written IMS Connect client application message structure can consist of one or more TCP/IP message structures.

Message structures returned to the client by the sample user message exit routine HWSSMPL1 (*SAMPL1*) start with LLLL, a 4-byte field that contains the total length of the message. The sample user message exit routine HWSSMPL0 (*SAMPLE*) does not add the LLLL field at the beginning of the message structures that it returns.

The output message from the message exit that is sent to user-written IMS Connect client applications is in one of the following formats:

Message format when the MFS MOD name is requested

The following table shows the format of the output message sent to the client application when the MFS MOD name is requested. The table provides information about the length and meaning of the fields in the output message.
Table 2. Output message format containing RMM, DATA, and CSM
Field Length Meaning
LLLL (HWSSMPL1 only) 4 bytes The total length of an output message returned by HWSSMPL1; output messages returned by HWSSMPL0 do not include this field
RMM header (optional) 20 bytes The first four bytes of the RMM are LLzz, the two byte length of the RMM and two bytes of binary zeros
CORTKN header (applicable to synchronous callout request) 52 bytes Correlation token for this synchronous callout request
Control data (applicable to synchronous callout request) n bytes Control data sent by the IMS application program
LL 2 bytes Length of data segment
zz 2 bytes Reserved (set to binary zeros)
DATA n bytes User data
LL 2 bytes Length of second data segment
zz 2 bytes Reserved (set to binary zeros)
DATA n bytes User data second data segment
...    
LL 2 bytes Length of nth segment
zz 2 bytes Reserved (set to binary zeros)
DATA n bytes User data nth data segment
CSM 12 bytes Complete status message

Message format when the MFS MOD name is not requested

The following table shows the format of the output message sent to the client application when the MFS MOD name is not requested and only data and the CSM are being sent. The table provides information about the length and meaning of the fields in the output message.

Table 3. Output Message format containing output data and CSM only
Field Length Meaning
LLLL (HWSSMPL1 only) 4 bytes The total length of an output message returned by HWSSMPL1; output messages returned by HWSSMPL0 do not include this field
CORTKN header (applicable to synchronous callout request) 52 bytes Correlation token for this synchronous callout request
Control data (applicable to synchronous callout request) n bytes Control data sent by the IMS application program
LL 2 bytes Length of data segment
zz 2 bytes Reserved (set to binary zeros)
DATA n bytes User data
LL 2 bytes Length of second data segment
zz 2 bytes Reserved (set to binary zeros)
DATA n bytes User data second data segment
...    
LL 2 bytes Length of nth segment
zz 2 bytes Reserved (set to binary zeros)
DATA n bytes User data nth data segment
CSM 12 bytes Complete status message

Format of an IMS command response message

The output message sent to a client submitting commands to the Operations Manager (OM) component of the IMS Common Service Layer (CSL) is shown in the following table. The table provides information about the length and meaning of the fields in the output message.

Table 4. Output message format sent to OM command client
Field Length Meaning
LLLL 4 bytes Length of output
DATA n bytes IMS command output