Re: Any tool that tells COM dependencies of a DLL?

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Actually that's what Igor was trying to tell you - the DLL never
gets unloaded even if the client never needs it anymore. It _can_
be unloaded in theory, but it never is in practice.

BTW, did you find COMSpy not helpful? I haven't used it
myself I admit...

--
=====================================
Alexander Nickolov
Microsoft MVP [VC], MCSD
email: agnickolov@xxxxxxxx
MVP VC FAQ: http://www.mvps.org/vcfaq
=====================================

"mysteron" <acornatom66@xxxxxxxxx> wrote in message
news:u5shdP2NGHA.1028@xxxxxxxxxxxxxxxxxxxxxxx
ok lets not nit pick here :) the scenario i was talking about is where the
client does a single cocreate, uses the interface and releases... all in a
short period of time.. the DLL gets unloaded shortly afterwards.. so my
point was that this loading/unloading is very dynamic .. and not something
that is easily followed just by keeping your eyes glued to process
explorer... also it might well happen in less time than the refresh rate
of that program, in which case you'd certainly see nothing ...
I see this behavior all the time when programming the windows vista
shell... dll's certainly *do* unload before the shell terminates... well
before...


"Igor Tandetnik" <itandetnik@xxxxxxxx> wrote in message
news:uMOeWL2NGHA.2696@xxxxxxxxxxxxxxxxxxxxxxx
"mysteron" <acornatom66@xxxxxxxxx> wrote in message
news:%23lQATo1NGHA.3064@xxxxxxxxxxxxxxxxxxxx
Also, even if the COM
object lives in a DLL.. that DLL will only be loaded into the process
space for the lifetime of the IUnkown pointer pased back from
cocreateinstance..

That's not true. Once loaded, COM DLLs are usually not unloaded until the
process is terminated, even when there are no outstanding references. In
principle, one can unload them explicitly by calling
CoFreeUnusedLibraries, but many people claim this function is actually a
no-op on modern OS versions (Win2K and above if I recall correctly).
--
With best wishes,
Igor Tandetnik

With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925





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