Re: [9fans] drawterm dies when my mac book sleeps by 9p design?

[Bakul Shah <bakul@bitblocks.com>]

On Sun, 06 Mar 2011 20:25:10 PST ron minnich <rminnich@gmail.com>  wrote:
> I used to work with David Mills, back long ago. He was one of the
> original Internet Buzzards, a really great guy. One of the many things
> he invented was NTP.

I wonder if he still owns a class B block of IP addresses :-)
[A friend did his PhD with him so we heard stories.]

> He would get pretty exercised about keep-alives. Felt that it was not
> the business of TCP to make these kinds of decisions. I can't remember
> if he actually called them an abomination, but at the same time, one
> was left with the feeling that he might have.

Agreed 100%. TCP is supposed to be resilient and not throw a
fit every time a link goes down.

> I never fully appreciated his argument until John DeGood described ham
> radio internet tcp sessions (this is also long ago) that would halt
> for days, then come back to life. That's pretty neat, and it can be
> hard if you are depending on keepalives. Just about any value you pick
> will be wrong.

A TCP connection is defined as <src-ip-addr, src-port,
dst-ip-addr, dst-port>. As long as these are in use, and a
path exists *when* a packet is to be sent, it is no one
else's business to consider it dead!

> So, yeah, they're out there and I guess nowadays everyone does them.
> Whether they are a good idea is somebody else's guess, I suppose. I
> note that today I slept my mac several times during this workshop and
> my ssh session was always there when I opened the lid again. That's
> nice.

I routinely leave ssh, xterm etc. alive for weeks on end and
my macbookpro puts itself to sleep a few times a day!  Even
when I used to take my laptop to work, no connexion broke as
long as avoided accidentally typing in the window (which would
generate traffic).