Path: utzoo!attcan!uunet!olivea!samsung!noose.ecn.purdue.edu!mentor.cc.purdue.edu!dls
From: dls@mentor.cc.purdue.edu (David L Stevens)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: Questions on TCP shutdown and RFC-793
Message-ID: <2539@mentor.cc.purdue.edu>
Date: 11 Dec 90 00:04:35 GMT
References: <36540017@hpindwa.cup.hp.com> <2452@mentor.cc.purdue.edu> <1990Dec10.131116.19393@jarvis.csri.toronto.edu> <2527@mentor.cc.purdue.edu>
Reply-To: dls@mentor.cc.purdue.edu (David L Stevens)
Organization: PUCC UNIX Group
Lines: 14


	More information: I looked briefly through our (4.3 Tahoe) code and
it does in fact appear to do shutdown(2) as the "half-close" that you (and
I) want it to do. That is, it doesn't deallocate the send buffer until the
final close and it does appear to go into TIME_WAIT, instead of just
deallocating the TCB.
	So, if you trust my cursory reading of the current code and you don't
take the documentation I quoted too literally, then shutdown(2) appears to
be safe after a write, even if it's buffered, in at least 4.3 Tahoe. :-)
	I unfortunately don't have time to look at it in detail enough to turn
the "appears to be safe" to just "is safe" right now, but if anyone else does,
I'd like to see what you find.
-- 
					+-DLS  (dls@mentor.cc.purdue.edu)