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Date: Mon, 14 Apr 2008 16:52:31 +0200
From: Ed Schouten <ed@80386.nl>
To: Jeff Roberson <jroberson@jroberson.net>
Message-ID: <20080414145231.GJ5934@hoeg.nl>
References: <1309.1208100178@critter.freebsd.dk> <20080413131724.X959@desktop>
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Subject: Re: f_offset
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* Jeff Roberson <jroberson@jroberson.net> wrote:
> You should use an sx lock which can be held across such operations.  Non=
=20
> seekable devices, terminals included, have to serialize all IO.  They are=
=20
> treated separately by posix.

It's all so confusing that the standards seem to change then. When I
take a look at the POSIX onlinepubs, the articles seem to mention the
opposite:

http://www.opengroup.org/onlinepubs/009695399/functions/read.html

	"The behavior of multiple concurrent reads on the same pipe,
	FIFO, or terminal device is unspecified."

http://www.opengroup.org/onlinepubs/009695399/functions/write.html

	"This volume of IEEE Std 1003.1-2001 does not specify behavior
	of concurrent writes to a file from multiple processes.
	Applications should use some form of concurrency control."

--=20
 Ed Schouten <ed@80386.nl>
 WWW: http://g-rave.nl/

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