Read/Write Large Binary File by API

Hello,
I am creating a file splitter in which I need to Split large files (up to 3 GB) in to small parts. I have tried to create one but in vb6 its not accepting file size more than arround 1GB. Even I want to do it fast.

There should be any API to read/write large file size..? Or any working example of a large file size splitter?


Thanks with Regards, :)