Re: Stats collection on Windows

On Wed, Apr 05, 2006 at 09:30:06AM +0200, Martijn van Oosterhout wrote:
> On Wed, Apr 05, 2006 at 03:20:47AM -0400, mark(at)mark(dot)mielke(dot)cc wrote:
> > TerminateProcess takes a HANDLE, not a process identifier. Yes, they
> > provide the "kill" primitive, but only as a compatibility measure. A
> > "good" Windows process, should maintain a HANDLE to the process, and
> > kill the process using the HANDLE. This way, there is no race. The
> > HANDLE is also how you wait for the process to terminate normally.
> Which presents the solution, we should use the HANDLE on windows rather
> than the process identifier.

Yes.

> > I prefer the "Redmond" way, in that I find UNIX's use of integer
> > identifiers to be encouraging of race conditions. UNIX requires hacks
> > like minimizing PID reuse, because UNIX is the one that is broken. :-)
> Eh? A HANDLE is (or can be mapped to) an integer too. I don't see
> anything on that page about handle reuse. If you run a machine long
> enough I'm sure it can be reused also...

Once upon a time, when I played with this stuff (I mostly use UNIX, not
Windows), I concluded to myself that HANDLE was process-local, and that
it was allocated. Meaning - it won't be re-used until you CloseHandle().
It's best then, to think of HANDLE as a opaque object. Regardless, of
whether it is process-local or not, until you run CloseHandle(), it is
yours to keep, and it won't be re-used.

Cheers,
mark

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