accessing parts of large files with File.seek()

[mhearne808[insert-at-sign-here]gmail[insert-dot-here]com]

On Aug 8, 7:37 pm, "programmer... at gmail.com" <programmer... at gmail.com>
wrote:
> On Aug 8, 11:46 am, "mhearne808[insert-at-sign-here]gmail[insert-dot-
>
>
>
> here]com" <mhearne... at gmail.com> wrote:
> > I'm having a problem with the File object's seek() method.
> > Specifically, I cannot use it to seek to a location in a binary file
> > that is greater than 2^31 (2147483648).  This seems unnecessarily
> > limiting, as it is common these days to have files larger than 2 GB.
>
> > Is there some LargeFile object out there that I can use to read my
> > file, which is approximately 3.3 GB in size?
>
> > Python version (freshly built from source this morning):
> > Python 2.5.1 (r251:54863, Aug  8 2007, 09:23:05)
> > [GCC 4.0.1 (Apple Computer, Inc. build 5363)] on darwin
>
> > Thanks,
>
> > Mike
>
> I use large files quite a bit, but in Windows & Linux.  Here's a quick
> excerpt of a local ubuntu-linux session...
>
> jaime at elizabeth:/var/virtualbox/VDI$ ls -l
> total 1682536
> -rw-rwx--- 1 jaime vboxusers      40960 2007-07-20 21:41 windows
> xp.vdi
> -rw-rwx--- 1 jaime vboxusers 3591387136 2007-07-20 21:53 winxp.vdi
> jaime at elizabeth:/var/virtualbox/VDI$ ipython
> Python 2.5.1 (r251:54863, May  2 2007, 16:27:44)
> Type "copyright", "credits" or "license" for more information.
>
> IPython 0.7.3 -- An enhanced Interactive Python.
> ?       -> Introduction to IPython's features.
> %magic  -> Information about IPython's 'magic' % functions.
> help    -> Python's own help system.
> object? -> Details about 'object'. ?object also works, ?? prints more.
>
> In [1]: f = file('winxp.vdi')
>
> In [2]: f.seek(3591387132)
>
> In [3]: f.read()
> Out[3]: '\x00\x00\x00\x00'
>
> In [4]:
>
> What exception are you receiving?  (Not that I can offer any advice,
> as I don't have a Mac to use for testing.)...
>
> jw

I think I've figured out what the problem must be (not at Mac anymore,
so will have to test tomorrow).  According to this link:
http://docs.python.org/lib/posix-large-files.html

I probably need to compile in large file support on my Mac.  I get it
for free on my Ubuntu linux box...

FYI, it was an OverFlow Error.