Subject: Re: TN3270E Flush Function

From: Gene Pullen <[email-masked]>
Date: Mon, 24 Nov 1997 09:59:56 -0600

Marty, I wanted to run this by you first.

I have a comment on the Flush mechanism debate.  I deleted the
other discussions.

At 10:04 AM 11/24/97 +1100, Derek W. Bolton wrote:
>>         Also, I'm a little unclear about the Flush mechanism.  I'm
>> uncomfortable with how it is defined.  I don't like all this
>> overloading or all of these special cases.  As a result of this and
>> other issues that have come up, I think we should look at adding an
>> extra byte (or stealing one of the lesser used bytes that's already
>> there) and start defining command/status bits or even adding new
>> TN3270E commands.  This would be a lot simpler than messing with
>> overloading of existing Telnet escape sequences.  I appreciate that
>> we're trying to actually "Abort some Output" here, but that doesn't
>> mean we should bend over backward to try and find a way to use
>> <IAC><AO>.
>
>How about a fragment of length 0 to indicate abort?

I like the idea of making it a fragment of length 0, but I would also
like to have a defined code that says exactly what this fragment is
trying to convey.  That way we can avoid misinterpretation of the
meaning of the "null" message.  I have seen clients send messages with
no data, and in the case of PRINT_EOJ from the server, I believe it is
usually sent sans data.  So I think it would be best to define a new
DATA_FLUSH data type/command code value to avoid overloading of a null
message as well.

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From: "Derek W. Bolton" <[email-masked]>
Date: Tue, 25 Nov 1997 08:08:53 +1100 (EST)

> DATA_FLUSH data type/command code value to avoid overloading of a null

Gene,

Yes, on second thoughts I agree with you.  A null fragment should
do nothing.

Regards,
  Derek