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Re: xAP EOM identifier in xAP v1.3



... Oh ... where is that in the spec ?  it might be all we need.

This is also tied in with some aspects of long message truncation
and concatenation of messages received in UDP receive buffers though...

K

Patrick Lidstone wrote:
>
>
> The original xap spec provides extensions for framing a message over
> async serial which also delimit the start of the message - you don't
> need this 'hack' if you follow the original spec for non-UDP
transports.
>
> Patrick
>
> 2009/9/13 Kevin Hawkins <yahoogroupskh@xxxxxxx
> <mailto:yahoogroupskh@xxxxxxx>>
>
>       We have been asked on several occasions how to detect the end of
a
>     xAP messager as there is no unique EOM character.  Typically in
any
>     reasonable sized packet structured transport eg UDP then the
packet
>     provides such an indication but on systems with small packets or
>     non eg
>     asynchronous serial this is not useable.
>
>       In discussing this with the specification team we must consider
>     backwards compatability and so we do not wish to alter the
>     specification
>     to include a unique EOM character.  What we do propose however is
that
>     xAP v1.3 will specify that all messages should end with two
>     consecutive
>     chr(10)'s immediately after the closing '}'
>
>     ie  ..... 7D 0A 0A
>
>      Some apps, even v1.2 ones,  already do this.  We don't believe
this
>     will cause any backwards compatibility issues and it will always
be
>     unique within a xAP message.
>
>      So, in developing xAP v1.3 apps could you therefore append  two
0A's
>     at the end of your messages , and of course handle incoming
messages
>     containing such.
>
>       K
>
>
>     ------------------------------------
>
>     Yahoo! Groups Links
>
>
>        mailto:xAP_developer-fullfeatured@xxxxxxx
>     <mailto:xAP_developer-fullfeatured@xxxxxxx>
>
>
>
>
>
>



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