Please, i need help!

I have mapped file to memory by standart way (CreateFile, CreateFileMapping,
MapView OfFile). But i need to increase size of this file in memory (e.g. i add new section to executable), can i doing this, and how to unmapview with new size (or it's impossible)? or better way to use buffers?

ps. i search answer in MSDN, but nothing found

If you need to grow a file mapping, you must first close the handles, then do a new CreateFileMapping with the increased size. When modifying PE executables, I tend to HeapAlloc a buffer of peheader.SizeOfImage bytes, then read in the executable data like the PE loader would - this is much easier for manipulating the image file.