[This message was posted by Hanno Klein of Deutsche Börse Systems <[email protected]> to the "4.4 Changes" discussion forum at http://fixprotocol.org/discuss/17. You can reply to it on-line at http://fixprotocol.org/discuss/read/1e5044b7 - PLEASE DO NOT REPLY BY MAIL.]
No, all fields within a message are either in the header, the body or the trailer, i.e. you have 3 groups of fields that have to come in this sequence. Within these main groups, only the header and trailer prescribes the sequencing of a subset of the fields as mentioned below (and Checksum has to be last field of trailer). You are right in that the tags in the body do not have to follow a sequence but I would see it as best practice to follow the sequence defined in the spec. That sequence follows a semantic and FIX users should adhere to FIX semantics. Technically, it does not matter but I find it helpful when reading an interface specification. A programmer has to come up with some sequence so why not just take the standard one. After all, it is available in the FIX repository (MsgContents.html, tag <Position>). With FIX 5, I believe another field (ApplVerID) becomes required in position four if application versioning is being used. Repeating groups also have sequencing rules for the tag=value syntax which are actually quite strict to enable parsing. First field is required and the rest have to appear in the pre-defined sequence. Regards, Hanno. > Hanno, > > After the first three fields of a FIX.4.4 message > > 8=FIX.4.4^9=BodyLength^35=MessageType^ > > there is no mention of positional field requirements for any other tags. > Isnt the remaining FIX message a "bag of Tags" ? > > Regards, > K. Mahesh > > > Only the first few fields of the header must be in sequence, see FIX > > Spec Volume 1. "The first three fields in the standard header are > > BeginString (tag #8) followed by BodyLength (tag #9) followed by > > MsgType (tag #35)." > > > > Also "General message format is composed of the standard header > > followed by the body followed by the standard trailer." > > > > Fields of the header thus must not appear in the body. [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 -~----------~----~----~----~------~----~------~--~---
