How to determine a process “virtual size” (WinXP)?

Question

I have a program that needs a lot of memory, and it crashes as soon as the 2GB virtual address space is reached. Sysinternals process explorer displays this as \"virtual si

Answer 1

I needed the same thing as theller, but unfortunately needed it for a process other than my own. Because of this, theller's self-answer of using "MEMORYSTATUSEX.ullTotalVirtual–MEMORYSTATUSEX.ullAvailVirtual" didn't work for me, since GlobalMemoryStatusEx() (the function that returns MEMORYSTATUXEX) only works for the current process.

So far, I've been unable to find exactly what I was looking for without using performance counters (I didn't get into those because they looked way more complex than what I was looking for). I got very close by looping around and using "VirtualQueryEx" to explore the address space of the desired process, counting up all of the regions that didn't have a State of MEM_FREE. In my tests, it seemed to be a constant 17M higher than I would have expected when comparing to Process Explorer. ...also, it is certainly not race-condition free.

Anyway, I know this is sorta a non-answer, but I figured I'd at least document the progress I'd made on this for whoever stumbles upon this next.