Max filesize for open on Knoppix 3.6

[weiss]

Hallo!

I have an Knoppix 3.6.
I create with mkiosfs an image greater then 2Gb and I check this image with checkmedia
(from SuSE9.3 suse/src/checkmedia-1.0-5.src.rpm compiled).
it is not possible to open this iso

if((fd = open(file, O_RDONLY)) == -1) return;

Is the function open limited to 2GB ?