ReadProcessMemory question

Robert Shearman rob at
Sat Nov 17 11:29:48 CST 2007

Dave Cartright wrote:
> I am trying to read the memory of another process with 
> ReadProcessmemory and I can only get it to work when I commit the 
> entire region I want to read with VirtualAllocEx - but as you probably 
> know when I do this it initializes the entire memory region to 0s.
> So my question is how do I get ReadProcessmemory to read from the region??

It sounds to me like you're trying to read the previous contents of 
areas of memory. However, you don't seem to realise either that virtual 
memory is not physical memory or that uncommitted virtual memory is not 
backed by a page of memory in swap or physical memory, so calling 
ReadProcessMemory on it doesn't make sense as there is no data there to 
be read! Furthermore, when a page of virtual memory is deallocated then 
it free to be allocated again by any process in the system, and as you 
say it is initialised to all 0's as a security measure and you can't get 
that same page back again.

Rob Shearman

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