Why Rebol Copy Big File fails with really big files whereas windows explorer doesn't?

I tried carl function http://www.rebol.com/article/0281.html

with 155 Mo it works.

Then I tested with 7 Go it fails without saying the limit.

Why is there a limit I can't see anything 开发者_开发问答in code that puts a limit.

There's no error message

>> copy-file to-rebol-file "D:\@mirror_ftp\cpmove.tar" to-rebol-file "D:\@mirror_ftp\testcopy.tar"
0:00
== none
>>

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REBOL uses 32-bit signed integers, so it can't read files bigger than 2147483647 bytes (2^31-1) which is roughly 2GB. REBOL3 uses 64-bit integers, so won't have such limitation.