Re: SEC_COMMIT usefulness in CreateFileMapping API



Windows CE does not use a page file, which means that non file-backed data (such as a memory mapped file without a base file in the filesystem) will never be paged out to disk.

See http://blogs.msdn.com/ce_base/archive/2008/01/19/Paging-and-the-Windows-CE-Paging-Pool.aspx


Good luck,

Michel Verhagen, eMVP
Check out my blog: http://GuruCE.com/blog

GuruCE
Microsoft Embedded Partner
http://GuruCE.com
Consultancy, training and development services.

curious1 wrote:
Hi All,

I am trying to understand importance of SEC_COMMIT section attibute when using CreateFileMapping API to share mapped file between two processes.

I am using hFile as INVALID_HANDLE_VALUE. which means no file is created in filesystem, so file will will be mapped into memory directly. How can I prevent this file frombeing paged out of memory and in case it is paged out, will the OS save this somewhere on filesystem ? How will this work if I have not given a valid file handle (basically no file exist in filesystem) ?

please help me understand this. I truly appreciate your time ...

thanks !

HANDLE CreateFileMapping(
HANDLE hFile, LPSECURITY_ATTRIBUTES lpFileMappingAttributes, DWORD flProtect, DWORD dwMaximumSizeHigh, DWORD dwMaximumSizeLow, LPCTSTR lpName );

.



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