CreateFileMapping Question

From: Bruce Kingsley (brucek5_at_mindspring.com)
Date: 05/21/04 

Date: Fri, 21 May 2004 02:38:29 GMT

All:

I have a question about the use of CreateFileMapping functions. See example
below...

First Process:

 HANDLE hmem = ::CreateFileMapping((HANDLE) 0xFFFFFFFF, NULL,
PAGE_READWRITE, 0, FileSize, FM_SCOPEMAPFILENAME);

 FileBuffer = (SampleTransferType*)::MapViewOfFile(hmem, FILE_MAP_WRITE, 0,
0, FileSize);

// Fill FileBuffer here....

 ::UnmapViewOfFile(FileBuffer);
 ::CloseHandle(hmem);

Second Process:

 HANDLE hmem = ::OpenFileMapping(FILE_MAP_WRITE, FALSE, FM_ADCMAPFILENAME);

 FileBuffer = (SampleTransferType*)::MapViewOfFile(hmem, FILE_MAP_WRITE, 0,
0, FileSize);

// FileBuffer is read here...

 ::UnmapViewOfFile(FileBuffer);
 ::CloseHandle(hmem);

All works, but I'm concerned about memory leaks. This code is repeatably
used and I wonder what frees the memory used by these functions? The first
process closes all it's handles before the second process opens the memory
file, so I know the memory is still be held. When the first process is
called again and calls CreateFileMapping with the same name, does it re-use
the same memory, or does it allocate even more memory? 

--
Regards;
Bruce Kingsley

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