[This message was posted by Naresh Maharaj of Instinet Europe plc
<[email protected]> to the "FAST Protocol" discussion forum at
http://fixprotocol.org/discuss/46. You can reply to it on-line at
http://fixprotocol.org/discuss/read/4a686b09 - PLEASE DO NOT REPLY BY MAIL.]
Please can you help with this query.
If I can get this resolved then it will further help in the logic and scope of
using the presence map.
I have a template as below:
[Please read “less than char“ as “(” and “greater than char” as “)”]
"(template name="StandardHeaderPart2")
(string name="ApplVerID" id="1128") (constant value="7"/) (/string)
(string name="SenderCompID" id="49") (copy/) (/string)
(string name="TargetCompID" id="56") (constant value="SWXGROUP-MDC"/)
(/string)
(uInt32 name="MsgSeqNum" id="34") (increment/) (/uInt32)
(string name="PossResend" id="97")(copy value="N"/)(/string)
(string name="SendingTime" id="52") (tail/) (/string)
(/template)"
And here is the data output that I see from the stream as I process the message.
[OUTPUT]
SenderCompID:SWXGROUP-MDI.P01|
MsgSeqNum:1290984|
PossResend:20090929-12:31:06.532|
SendingTime
Note the PossResend was not in the stream so the next entity read inadvertently
was the Sendtime and this was added the field PossResend. This happened because
there was no way to determine if the PossResend value was in the stream or not.
If indicated then I would have read the next data entity as the field
SendingTime instead.
I refer to the template above and the line:
(string name="PossResend" id="97")(copy value="N"/)(/string)
The FAST Spec confirms the copy operator value of a field can be optional and
may or may not be in the stream.
So I intepret this as :-
"if not in the stream add 'N' as part of your message construction".
"else if present in the stream use and copy the value".
The question is :- How do I determine if present in the stream?
Do I use the presence map in the messsage to determine if the PossResend is in
the stream?
Or is the Presence map bits reserved only for fields that have the optional tag?
e.g. below:
(string name="MDExecTime" id="6572" presence="optional") (tail/)
Regards
Naresh
[You can unsubscribe from this discussion group by sending a message to
mailto:[email protected]]
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Financial Information eXchange" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/fix-protocol?hl=en
-~----------~----~----~----~------~----~------~--~---
