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From: michaud@decvax.dec.com (Jeff Michaud)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: 'shutdown' vs. 'close' to free resources?
Keywords: tcp shutdown socket
Message-ID: <5509@shlump.nac.dec.com>
Date: 18 Oct 89 20:43:31 GMT
References: <4577@mentor.cc.purdue.edu> <239@melpar.UUCP>
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Lines: 16

> Close(2) is the only way to
> guarantee delivery of all pending written data short of doing this in
the upper
> protocol.

	Note that, at least in the OSI model, transport isn't really the right layer
	to do "orderly release".  "Orderly release" is a job for the OSI
Session layer.
	Since on the IP stack we really don't have a Session layer, it should be done
	in another higher layer (ie. the application protocol).  For example, both
	FTP and SMTP have an explicit release handshake.

/--------------------------------------------------------------\
|Jeff Michaud    michaud@decwrl.dec.com  michaud@decvax.dec.com|
|DECnet-ULTRIX   #include <standard/disclaimer.h>              |
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