Re: Want COM to use a running DLL, not load it again

From:
"Igor Tandetnik" <itandetnik@mvps.org>
Newsgroups:
microsoft.public.vc.atl
Date:
Wed, 6 Jun 2007 00:51:28 -0400
Message-ID:
<#DcYTZ$pHHA.1144@TK2MSFTNGP02.phx.gbl>
"Scott McPhillips [MVP]" <org-dot-mvps-at-scottmcp> wrote in message
news:sLGdnb2VW4lNjPvbnZ2dnUVZ_vOlnZ2d@comcast.com

My COM object is defined and registered by a DLL. The DLL is loaded
by a running exe. (They're eventually going to be an always-running
service.)
When I attempt to CoCreateInstance from an external process I want it
to create the object in the running exe process. But it is loading a
new instance of the DLL into my process and creating the object there.

It looks like the CLSCTX_LOCAL_SERVER flag is sort of what I need, but
the docs say it is for an exe server. What I have is an exe process
(currently with no COM) that has loaded a DLL server that does support
COM. Is there some way I can get more control of where COM creates
the object?


Try calling CoRegisterClassObject from the process that first loaded the
DLL. After that, CoCreateInstance(CLSCTX_LOCAL_SERVER) from another
process should work.

I can't help but wonder - why don't you just implement the object in an
out-of-proc (EXE) server in the first place? What's the point of having
a DLL if you don't want it loaded by clients?
--
With best wishes,
    Igor Tandetnik

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