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Message-ID: <01cc01c24d10$f3b499b0$6132bc3e@BABEL>
From: "Conrad Scott" <Conrad DOT Scott AT dsl DOT pipex DOT com>
To: <cygwin-developers AT cygwin DOT com>
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Subject: Re: readv/writev
Date: Mon, 26 Aug 2002 15:57:51 +0100
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"Corinna Vinschen" <vinschen AT redhat DOT com> wrote:
>
> On Mon, Aug 26, 2002 at 03:20:00PM +0100, Conrad Scott wrote:
> >
> > At the coal-face it ends up being a bit more messy than that.
For
> > example, the fhandler::read code checks the readahead buffers
for
> > pending data but they will always be empty in binary-mode
(AFAIK)
> > . In fact there's a page of code before the check for whether
a
> > binary read is being done and only then does the code escape
back
> > to the caller.  Since (AFAIK) you can't change the text/binary
> > mode of an fd once it's been opened (and thus the readahead
>
> You can.  setmode(fd, O_TEXT); or setmode(fd, O_BINARY);

Sorry: I'd missed that in my meanderings about the source.  Thanks
for the pointer.

And as for my comments about the readahead buffer in text-mode
handling: well, I was only thinking about "fast" devices; you
couldn't just flush the readahead in general.  Even if the
text-mode support were removed from fhandler_serial, as Chris
suggested, there're still pipes to worry about.

So, I'll go and worry about something else instead :-)

// Conrad