Message-ID: <3417996D.6E5C@bo.dada.it>
Date: Thu, 11 Sep 1997 09:10:37 +0200
From: Diego Zuccato <dz AT bo DOT dada DOT it>
Organization: CyberSpace Software Labs BBS
MIME-Version: 1.0
To: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
CC: djgpp-workers AT delorie DOT com
Subject: Re: Transfer buffer (Was: Re: fread slowstart)
References: <Pine DOT SUN DOT 3 DOT 91 DOT 970910165039 DOT 10485B-100000 AT is>
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Eli Zaretskii wrote:

> > It's not possible that a tb is altered out of libc contol, right ?
> Wrong.  Application code is free to use the transfer buffer also.
Not inside a call to a libc function. So all the functions know when the
tb could be altered. Using it for an asyncronous event (like an IRQ) is
a Real Bad Thing, IMHO ... So it could really be better if the two
buffers (libc one and application one) are different.

> > I don't remember libc functions that assume that tb isn't altered.
> I don't think any of them do, right now.  But this doesn't change
> anything, because having the contents of tb change under your feet is
> IMHO a Bad Thing.  It requires the library maintainer to be acutely aware
> at all times that such a possibility exists, and that ain't easy.
tb doesen't change under your feet. Its contents could change only when
invoking another program. And if now no function assumes it's constant
during a call, let's document that it can change during some calls.