Re: [Boost-users] [Interprocess] [file_mapping] is there any way to avoid writing a modified file to disc?

On Thu, Dec 8, 2011 at 12:19 AM, Thorsten Ottosen wrote:

Hi,

I'm using file_mapping/mapped_region with Boost 1.45. My idea was to load the memory mapped file in read/write mode and then decrypt the file content in-place (to avoid copying the entire file content). However, this will save a decrypted file :-(

Is there any way to avoid the file being saved after in-memory manipulation?

In POSIX there's a way to say that a read/write region can be declared private -- changes to it would not be propagated to the underlying file. I don't see a way from the docs of providing the MAP_PRIVATE flag to the call to mmap. Not sure if there's a similar concept in Windows. Cheers -- Dean Michael Berris http://goo.gl/CKCJX