From: Thomas Demmer <demmer AT LSTM DOT Ruhr-UNI-Bochum DOT De>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: read / write   errors
Date: Sun, 28 Dec 1997 19:02:08 +0100
Organization: Lehrstuhl fuer Stroemungsmechanik
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Steve Patton wrote:
> 
> I am making an archive program, that uses (has nothing to do with the
> problem, but is using Allegro Compression Routines).  And here's what I do.
> 
[.:.]

> of course that's a snippet, with (hopefully) all you need to know.  It works
> with the first file, perfectly.  However, when it gets to the second, or
> more file, read does not read (or at least return) the correct size.  Such
> as the second file, it only says it read 690 bytes or so, when it's about
> 55,000 bytes, and then the next read returns 0, as if it were at the end of
> file.  The error (which is odd), I switched all read calls, with _dos_read
> calls (which should be compatible, since they are handle operated), and it
> works just fine.  How come "read" doesn't work correctly?  Who would I
> report this error too?
In DOS you must add O_BINARY to the open call. Otherwise, it'll
change all occurences of CR/LF to LF on read and vice versa on
write. And (and this is your problem) it terminates when
it hits a Ctrl-Z. 

BTW, this code looks like C++, so once your at it, why not use
the stream functions? Although this is just aesthetic and you'll
hit the same problem there (and maybe others...)


-- 
Ciao
Tom

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* Thomas Demmer                                             *
* Lehrstuhl fuer Stroemungsmechanik                         *
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