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<== Date ==> <== Thread ==>

Subject: RE: Variable size frame
From: "Jeff Hill" <[email protected]>
To: "'Bruno Coudoin'" <[email protected]>, <[email protected]>
Date: Wed, 4 Mar 2009 11:03:09 -0700
Hello Bruno,

The maximum array size transmitted is determined by what you service snap in
returns from casPV :: maxBound ( 0 ). We will call that NS.

With the current state of the CA protocol the client can request a number of
elements NE constrained by 0 < NE <= NS. The number of elements NE can be
specified when making a get, put, or subscription request. As I recall, if
the number of elements provided by the service snap in is less than what the
client has requested then the client does not receive status indicating an
error, and instead it will receive the number of elements it has requested
with the undefined elements (at the end of the array) being set to zero.
Note also that if the client subscribes specifying an element count NE then
that number of elements will not change, but the client always has an option
of canceling the subscription and starting a new one specifying a different
NE.

That?s the current state of things. We will certainly need to consider the
need for improved flexibility in the future. 

Jeff

> -----Original Message-----
> From: [email protected] [mailto:[email protected]]
> On Behalf Of Bruno Coudoin
> Sent: Tuesday, March 03, 2009 3:39 PM
> To: [email protected]
> Subject: Variable size frame
> 
> 
> >From a CAS server, I am sending an array PV. I found out that the frame
> being sent on the wires has the size of the maximum array bounds and not
> the actual transmitted array size.
> 
> Is this the normal behaviour or is there a way to be more efficient in
> case where the payload size is changing?
> 
> --
> Bruno Coudoin
> http://gcompris.net  Free educational software for kids
> http://toulibre.org  Logiciel Libre à Toulouse
> http://april.org     Promouvoir et défendre le Logiciel Libre




Replies:
RE: Variable size frame Bruno Coudoin
References:
Variable size frame Bruno Coudoin

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