hSection is a handle to a file mapping object that the function will use to create the DIB and can be NULL. If hSection is not NULL, it must be a handle to a file mapping object created by calling the CreateFileMapping function (otherwise CreateDIBSection will fail). Moreover, the CreateDIBSection function will locate the bitmap’s bit values at offset dwOffset in the file mapping object referred to by hSection. An application can retrieve the hSection handle by calling the GetObject function with the HBITMAP returned by CreateDIBSection.

hMapFile = CreateFileMapping(INVALID_HANDLE_VALUE, 0, PAGE_READWRITE, 0, 4096, "mIRC")

static extern IntPtr CreateFileMapping(IntPtr hFile,