Set a stream to global memory

[aewarnick]

What is the best was to set a stream to global memory but have the flexibility to use the same kind of stream to read from a file?

I tried this:

filebuf fb;
fb.setbuf((char*)pBuffer, ::GlobalSize(hGlbl));
istream* s(fb);
this->FromStream(s);

But I cannot access setbuf. And I don't want to use IStream. I cannot compile it and I didn't see any MS reference to the lib it is defined in.