Re: Trouble writing very large files [message #64820 is a reply to message #64729] |
Thu, 15 January 2009 19:35  |
Andrew Cool
Messages: 219 Registered: January 1996
|
Senior Member |
|
|
On Jan 16, 6:39 am, wlandsman <wlands...@gmail.com> wrote:
> Vince Hradil posted a message in September about problems writing
> large files. I am encountering the same problem, but with a
> variation. Instead of giving a segmentation fault, IDL returns
> without writing anything.
>
> IDL> print,!version
> { x86_64 linux unix linux 7.0 Oct 25 2007 64 64}
> IDL> im = intarr(4096,4096,256)
> IDL> openw,1,'test.dat'
> IDL> writeu,1,im
> IDL> close,1
> IDL> $ls -l test.dat
> -rw-r--r-- 1 wlandsma shadow 0 2009-01-15 15:22 test.dat
>
> If I instead do the same thing with a 4096 x 4096 x 255 array, then
> IDL does crash with a segmentation fault. My guess is that an
> internal IDL counter is not properly defined as 64 bit integer, and
> so is being set to zero in my first case (where subscripts are a exact
> multiple of two). In the second case it is being set to a negative
> number and causing IDL to crash.
>
> In any case this seems to be an internal IDL bug, since I should be
> able to write these arrays on a 64 bit machine. --Wayne
Wayne,
A similarly interesting response at the command line ;-
IDL Version 6.4, Microsoft Windows (Win32 x86 m32). (c) 2007, ITT
Visual Information Solutions
Installation number: 100512.
Licensed for use by: Surv Systems Div, DSTO
IDL> print,4096L*4096L*256L
0
IDL> print,4096L*4096L*255L
-16777216
And that's 32 bit Win.
Andrew
|
|
|