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Re: NCSA implementation of KeepAlive

From: Henrik Frystyk Nielsen <frystyk@w3.org>
Date: Sat, 21 Oct 1995 19:17:10 -0400
Message-Id: <9510212317.AA07695@www20>
To: "Roy T. Fielding" <fielding@avron.ICS.UCI.EDU>
Cc: Jeffrey Mogul <mogul@pa.dec.com>, http-wg%cuckoo.hpl.hp.com@hplb.hpl.hp.com

> > (2) The Spyglass browser ignores this header, the NCSA browser
> > apparently ignores it, and nobody else's browser seems to pay
> > any attention, either.
> 
> As I said before, it carries *diagnostic* information.  You don't have
> to send it, and you don't have to read it, but if you happen to be running
> a server for the purpose of testing client behavior (or running a client
> in order to test a server implementation) it can be quite useful if
> the server is using an adaptive timeout/request scheme to be able to
> see the choices without forcing an actual timeout.

Also remember that the browsers mentioned who support this (NCSA, Spyglass and 
the ones using W3C Reference library) all use non-blocking sockets where 
catching a closing socket using select is very easy. If you are using blocking 
sockets (what many basic applications do) then it is not so easy and requires 
that you start catching SIG_PIPE signals (or equivalent). In this case any 
information on what to expect from the connection is most useful.

-- 

Henrik Frystyk Nielsen, <frystyk@w3.org>
World-Wide Web Consortium, MIT/LCS NE43-356
545 Technology Square, Cambridge MA 02139, USA
Received on Saturday, 21 October 1995 16:26:29 EDT

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