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From: David on 4 Jul 2005 04:45
Hiýý

I have a question about my VC6 app.
I read a huge binary file, which is >4GB.
An exception will throwed when I run to the code below:

....
CFile fileSrc(strSrcFilePath,CFile::modeRead);
dwSrcLen = (unsigned long)fileSrc.GetLength(); <--- this row of code results
in error!
....

My app hangs in EINCORE.CPP, and the debug message is:
CFile exception: generic, File Unknown, OS error information = 87.

Any helps? Thanks.



From: Scot T Brennecke on 4 Jul 2005 06:47
David,
You do know that the largest integer that can be stored in a 32-
bit unsigned long is 4 gig, right? So, clearly you are not going to get
the value you want into a DWORD. I don't remember how GetLength() is
defined in VC6, but in VC7.1, it's a ULONGLONG (64-bit unsigned).
I don't know what the file EINCORE.CPP is, but I'm pretty sure
it's not part of the MFC source.

In article <ubAoRPHgFHA.3304(a)TK2MSFTNGP12.phx.gbl>,
David_Wang_Xian(a)hotmail.com says...
> I have a question about my VC6 app.
> I read a huge binary file, which is >4GB.
> An exception will throwed when I run to the code below:
>
> ...
> CFile fileSrc(strSrcFilePath,CFile::modeRead);
> dwSrcLen = (unsigned long)fileSrc.GetLength(); <--- this row of code results
> in error!
> ...
>
> My app hangs in EINCORE.CPP, and the debug message is:
> CFile exception: generic, File Unknown, OS error information = 87.
From: David on 5 Jul 2005 03:36
Sorry for my spelling mistake: not EINCORE.CPP, but WINCORE.CPP, which is
part of MFC.
In VC6, return value of GetLength() is defined as DWORD. Then, what can I do
to get length of huge file?
Thanks.

"Scot T Brennecke" <ScotBspamhater(a)MVPs.org> ????
news:MPG.1d32cfdb6059d7ff989c62(a)msnews.microsoft.com...
> David,
> You do know that the largest integer that can be stored in a 32-
> bit unsigned long is 4 gig, right? So, clearly you are not going to get
> the value you want into a DWORD. I don't remember how GetLength() is
> defined in VC6, but in VC7.1, it's a ULONGLONG (64-bit unsigned).
> I don't know what the file EINCORE.CPP is, but I'm pretty sure
> it's not part of the MFC source.
>
> In article <ubAoRPHgFHA.3304(a)TK2MSFTNGP12.phx.gbl>,
> David_Wang_Xian(a)hotmail.com says...
> > I have a question about my VC6 app.
> > I read a huge binary file, which is >4GB.
> > An exception will throwed when I run to the code below:
> >
> > ...
> > CFile fileSrc(strSrcFilePath,CFile::modeRead);
> > dwSrcLen = (unsigned long)fileSrc.GetLength(); <--- this row of code
results
> > in error!
> > ...
> >
> > My app hangs in EINCORE.CPP, and the debug message is:
> > CFile exception: generic, File Unknown, OS error information = 87.


From: Joseph M. Newcomer on 5 Jul 2005 11:15
Use the raw API to do this.

LARGE_INTEGER length;

then either
length.LowPart = ::GetFileSize(fileSrc.m_hFile, &length.HighPart);

or

::GetFileSizeEx(fileSrc.m_hFile, &length);

in either case, you will have the file length in length.QuadPart.

Microsoft has had a lot of problems getting MFC to "grow up" to the 32-bit world, and this
is one of the more egregious failures. It only took about a decade to get this problem
fixed in VS7.

Note that according to the docs, m_hFile is declared a UINT, so I think you may have to
add a (HANDLE) cast to it to get the above to compile.
joe

On Tue, 5 Jul 2005 15:36:15 +0800, "David" <David_Wang_Xian(a)hotmail.com> wrote:

>Sorry for my spelling mistake: not EINCORE.CPP, but WINCORE.CPP, which is
>part of MFC.
>In VC6, return value of GetLength() is defined as DWORD. Then, what can I do
>to get length of huge file?
>Thanks.
>
>"Scot T Brennecke" <ScotBspamhater(a)MVPs.org> ????
>news:MPG.1d32cfdb6059d7ff989c62(a)msnews.microsoft.com...
>> David,
>> You do know that the largest integer that can be stored in a 32-
>> bit unsigned long is 4 gig, right? So, clearly you are not going to get
>> the value you want into a DWORD. I don't remember how GetLength() is
>> defined in VC6, but in VC7.1, it's a ULONGLONG (64-bit unsigned).
>> I don't know what the file EINCORE.CPP is, but I'm pretty sure
>> it's not part of the MFC source.
>>
>> In article <ubAoRPHgFHA.3304(a)TK2MSFTNGP12.phx.gbl>,
>> David_Wang_Xian(a)hotmail.com says...
>> > I have a question about my VC6 app.
>> > I read a huge binary file, which is >4GB.
>> > An exception will throwed when I run to the code below:
>> >
>> > ...
>> > CFile fileSrc(strSrcFilePath,CFile::modeRead);
>> > dwSrcLen = (unsigned long)fileSrc.GetLength(); <--- this row of code
>results
>> > in error!
>> > ...
>> >
>> > My app hangs in EINCORE.CPP, and the debug message is:
>> > CFile exception: generic, File Unknown, OS error information = 87.
>

Joseph M. Newcomer [MVP]
email: newcomer(a)flounder.com
Web: http://www.flounder.com
MVP Tips: http://www.flounder.com/mvp_tips.htm
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