Re: holding connections open: oh, well

Karl Auerbach (karl@cavebear.com)
Fri, 16 Sep 1994 19:28:59 +0200

> A couple of people have beat into my feeble brain the show-stopper
> problem with my modest proposal: not all servers reliably return
> Content-Length in response to each GET. Therefore clients rely on
> getting EOF (i.e., a dropped connection) to know when they've gotten
> everything. Which means, therefore, that servers can't hold open a
> connection, or the client will keep waiting until it times out.
>
> So, with apologies to all for the chatter and bandwidth, I withdraw my
> modest proposal. (Gee, it seemed like such a good idea at the time.)

Don't give up yet. There are lots of ways to handle indeterminate
length input. My favorite is to "chunk" the stream so that it comes
as a sequence of determinate length segments. (One can almost always
know how long each intermediate chunk is, i.e. the size of the
transmit buffer in the absence of any other information).

It has a nice ancillary property in that it can allow restart of
broken transmissions of huge items (not that anybody has done that
yet.)

--karl--