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From: Manuel Collado <m DOT collado AT invalid DOT domain>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Open large file gives EACCES
Date: Tue, 23 Feb 2010 10:03:23 +0100
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Rugxulo escribió:
> Hi,
> 
> On Feb 21, 6:51 pm, nob DOT  DOT  DOT  AT xmission DOT com (Scott) wrote:
>> Using DJGPP (2.03, GCC 3.3.3 dated 16-Feb-2004, LIBC dated 24-Dec-2001) in a
>> WinXP command shell.
>>
>> Trying to fopen a large (8Gb) file in "rb" mode, I get a fail with EACCES,
>> although perms are OK and no locks exist.  Is this expected behavior with
>> large files?  I know I'm overstepping the limits of an MSDOS program, but I
>> figured that I would at least be able to read the file serially, since it
>> was *created* with a DJGPP program using fopen/fwrite.
> 
> I have no experience with large files since I tend to avoid them. In
> lieu of a response from CWS (so far), I'll just say that he has
> claimed before that 2.04 beta has "better 4 GB file support". So try
> that.   ;-)

I've not worked with very large files with DJGPP, but I've experienced 
related problems in another context (Cygwin). There is a potential 
overflow if byte counts (file length, offset, ...) are stored in 32 bit 
variables. The absolute limits are:

- signed values  : 2^31-1 = 2147483647 Bytes ~= 2.15 GB
- unsigned values: 2^32-1 = 4294967295 Bytes ~= 4.29 GB

Just a thought.
-- 
Manuel Collado - http://lml.ls.fi.upm.es/~mcollado