Creating Smaller Memory-Mapped Views on a Huge 2G+ File

[Frank Chang]

Good afternoon, I have written a C++ class for Windows and Linux that creates a memory-mapped view for an file of arbitrary size n. The code for the class constructor is in the www.pastebin.com url shown below.
I am currently testing the code on Windows 32 bit XP.
I have found for file sizes 0 < n <= 1.7GB , the constructor returns a valid pointer to a memory-mapped view. However, for a file size >= 2 GB, MapViewOfFile returns a NULL value and an error code of 8,"Not enough storage is available to process this command". Evidently, Windows cannot find an available address space of size 2 GB in the process.
Therefore, I may need to modify the class constructor to create a set of smaller memory-mapped views totaling >= 2GB bytes && < 2 ^ 32 - 1 bytes. The other requirement is to create a mapping between each of the smaller memory-mapped views and a randomly accessed address in the process' address space.
Previously, I used the following code for random access:
char* KeyArray;

try {
mmapFile = new cMemoryMappedFile(n);
}
catch (cException e)
{
throw;
}

KeyArray = (char *)(mmapFile->GetPointer());
KeyArray[i] = ...


How should I modify the class to handle these requirements? Thank you.

<iframe src="http://pastebin.com/embed_iframe.php?i=2GX0XHsm" style="border:none;width:100%"></iframe>

[Rabbit]

In 32 bit Windows, you can't go over 2 gigs. You have to use 64 bit if you want to address memory over 2 gigs.

[Jason Mortmer]

Actually just under 4GB is the maximum size.

[Rabbit]

You're right, my bad. I knew it yet I posted without thinking about it.