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Re: 64-bit file operations (lseek64() etc) misbehaving
Hi Igor,
Yes the a.out a.exe thing is a typo. I've read the page on special
filenames. You can use the POSIX names or you can open the Windows
device namespace name. Either way, my problem isn't with opening and
reading from the disk device. That works fine. My problem is with
lseek() not being able to seek past the 4Gb boundary.
Thanks.
On Wed, Mar 31, 2004 at 02:14:18PM -0500, Igor Pechtchanski wrote:
> On Wed, 31 Mar 2004, Mike Brown wrote:
>
> > Hi,
> >
> > cygwin 1.5.9-1 on Windows XP Service Pack 1.
> >
> > I need 64-bit versions of lseek() and friends. No prototype exists for
> > lseek64(). I've searched the archives on the list and many claim that
> > 64-bit support is "automatic" and lseek() resolves at compile time to
> > lseek64(). This isn't happening for me. Is there a compile time
> > define I need to make this happen?
> >
> > [snip]
> > Here's a simple example app I'm using. I run via: a.out PhysicalDrive0
>
> Michael,
>
> I don't know if it's related to the problem you're having, but I'm sure
> you've read <http://cygwin.com/cygwin-ug-net/using-specialnames.html>,
> right? Try compiling a Linux version with "#define lseek64 lseek", and
> use ./a.exe /dev/sda (note that Cygwin gcc produces a.exe, not a.out, by
> default, so I assume the above is a typo or the result of an explicit "-o"
> flag).
> Igor
>
> > -----------------------
> > /* #define LINUX */
> > #define WIN32
> >
> > [snip]
> > #ifdef WIN32
> > /* automatically add the \\.\ crap in front */
> > sprintf(filename, "\\\\.\\%s", argv[1]);
> > #else
> > sprintf(filename, "%s", argv[1]);
> > #endif
> > [snip]
> > #ifdef WIN32
> > maxblock = lseek(fd, 0, SEEK_END);
> > #else
> > maxblock = lseek64(fd, 0, SEEK_END);
> > #endif
>
> --
> http://cs.nyu.edu/~pechtcha/
> |\ _,,,---,,_ pechtcha@cs.nyu.edu
> ZZZzz /,`.-'`' -. ;-;;,_ igor@watson.ibm.com
> |,4- ) )-,_. ,\ ( `'-' Igor Pechtchanski, Ph.D.
> '---''(_/--' `-'\_) fL a.k.a JaguaR-R-R-r-r-r-.-.-. Meow!
>
> "I have since come to realize that being between your mentor and his route
> to the bathroom is a major career booster." -- Patrick Naughton
-Michael F. Brown, EMC Corp.
Email: mbrown@emc.com
EMC Tie Line: 824 25924
External Line: (508) 382-5924
"5 years from now everyone will be running free
GNU on their 200 MIPS, 64M SPARCstation-5." -Andrew Tanenbaum '92
(In late 1997 I installed Linux for the first time on my 200Mhz, 128M
AMD x86 clone)
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