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From: "Daniel C. Sobral" <dcs@gns.com.br>
Message-Id: <199801251452.MAA00740@daniel.sobral>
Subject: uiomove()
In-Reply-To: <199801241656.IAA24947@hub.freebsd.org> from freebsd-hackers-digest at "Jan 24, 98 08:56:16 am"
To: hackers@FreeBSD.ORG
Date: Sun, 25 Jan 1998 12:52:12 -0200 (EDT)
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> OK.  Here's a more "politically correct" read() routine.  You should be 
> able to mirror this into a write() fairly easily.
> 
[snip]
> 			if (result = ERESTART)
> 				if (got == 0)
> 					result = 0;
> 				else
> 					result = EINTR;
[snip]
> 
> You might want to always convert ERESTART to EINTR (always error on 
> interrupt), but that becomes more complex as you may already have 
> consumed data from the read buffer, which may throw your caller out of 
> sync.
> 
> Another approach is to ignore ERESTART, ie. never return a short count.
> That's also quite legitimate with the above code, ie. 
> 
> 	if (result == ERESTART) 
> 		result = 0;

I don't quite get it. My code can actually restart at any point,
except for struture uio. What's the _purpose_ of ERESTART?

-- 
Daniel C. Sobral		  (8-DCS)
dcs@gns.com.br

There was a young gaucho named Bruno
Who said, "There is one thing I do know,
	Women are fine
	And children devine,
But the llama is numero uno."