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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: <2452@mentor.cc.purdue.edu>
Date: 8 Dec 90 11:52:13 GMT
References: <36540017@hpindwa.cup.hp.com>
Reply-To: dls@mentor.cc.purdue.edu (David L Stevens)
Organization: PUCC UNIX Group
Lines: 15


	If you check in the beginning of the "SEGMENT ARRIVES" section of
RFC 793, it says that they assume packets have already been sequenced in
proper order for the rest of it.
	Re: shutdown(2) in BSD implementations. It corresponds roughly to
the TCP ABORT function, but not quite. In particular, as the manual page
says, any buffered data pending will be dropped. It isn't really the
"half close" that RFC 793 wants, and it should only be used in programs
that are aborting or, because of mechanisms in the application protocol,
already know that the data has been delivered. It should *not* be used for
applications that have done writes and just want to mark the end of data for
the peer, since any data still pending in the local send buffers is discarded
and never delivered.
-- 
					+-DLS  (dls@mentor.cc.purdue.edu)