Is there a COM object that just implements IUnknown I can use?

Posted by Matt on Stack Overflow See other posts from Stack Overflow or by Matt
Published on 2012-09-03T23:15:52Z Indexed on 2012/09/04 3:38 UTC
Read the original article Hit count: 388

Filed under:

com

|

iunknown

For an asynchronous Windows API, I can provide an IUnknown state parameter to associate calls to the API with calls from the callback.

It's my understanding that COM guarantees that two IUnknown pointers to the same object will be of the same value. Thus, if I only want to associate API calls with callbacks, IUnknown should be all I need, by comparing the values of the pointers.

Is there a stock implementation of IUnknown I can use? Of course it would be trivial to implement myself, but for such a base component of COM, I'm wondering if Windows or ATL provides one I should use instead.

Thanks, --Matt

© Stack Overflow or respective owner

Related posts about com

Cannot update, apt-get cannot fetch index files

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I have a fresh install of Ubuntu 11.10 from the iso 'ubuntu-11.10-desktop-amd64.iso'. I installed this in VMWare Fusion 4.1.1 running on OSX 10.7.3. When setting up the VM, I allowed easy install to take care of creating my user and installing VMWare tools. No problems during installation, everything… >>> More
'sudo apt-get update' error

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I've been having an issue with 'sudo apt-get update' for several days now. I've tried every proposed solution I could find but to no avail. Here is the output to 'apt-get update'. Ign http://us.archive.ubuntu.com precise InRelease Ign http://us.archive.ubuntu.com precise-updates… >>> More
I have finally traded my Blackberry in for a Droid!

as seen on Geeks with Blogs - Search for 'Geeks with Blogs'
Over the years I have used a number of different types of phones. Windows Mobile, Blackberry, Nokia, and now Android. Until the Blackberry, which was my last phone (and I still have one issued from my office) I had never found a phone that “just worked” especially with email and messaging. The Blackberry… >>> More
"Something wicked happened" error in apt-get

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
Everytime I try to install through terminal I get this" I am not able to install or update and I can't find working answer for this here. Here is my apt-get update result: Hit http://ppa.launchpad.net raring Release.gpg Hit http://deb.opera.com stable Release.gpg… >>> More
Split a long JSON string into lines in Ruby

as seen on Stack Overflow - Search for 'Stack Overflow'
First, the background: I'm writing a Ruby app that uses SendGrid to send mass emails. SendGrid uses a custom email header (in JSON format) to set recipients, values to substitute, etc. SendGrid's documentation recommends splitting up the header so that the lines are shorter than 1,000 bytes. My… >>> More

Related posts about iunknown

COM IUnknown and do I need a pointer to it first before calling CoGetClassObject?

as seen on Stack Overflow - Search for 'Stack Overflow'
In COM, when you want to create an instance of some COM Server object, do you first need to get a pointer to it's IUnknown interface and only then create a class object using CoGetClassObject? As far as I understand it, IUnknown is used to manage object lifetimes, so from my understanding, whatever… >>> More
Is there a COM object that just implements IUnknown I can use?

as seen on Stack Overflow - Search for 'Stack Overflow'
For an asynchronous Windows API, I can provide an IUnknown state parameter to associate calls to the API with calls from the callback. It's my understanding that COM guarantees that two IUnknown pointers to the same object will be of the same value. Thus, if I only want to associate API calls with… >>> More
Hook IDispatch v-table in C++

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm trying to modify the behavior of an IDispatch interface already present in the system. To do this my plan was to hook into the objects v-table during runtime and modify the pointers so it points to a custom hook method instead. If I can get this to work I can add new methods and properties to… >>> More
Using mem_fun_ref with boost::shared_ptr

as seen on Stack Overflow - Search for 'Stack Overflow'
Following the advice of this page, I'm trying to get shared_ptr to call IUnknown::Release() instead of delete: IDirectDrawSurface* dds; ... //Allocate dds return shared_ptr<IDirectDrawSurface>(dds, mem_fun_ref(&IUnknown::Release)); error C2784: 'std::const_mem_fun1_ref_t<_Result… >>> More
"Win32 exception occurred releasing IUnknown at..." error using Pylons and WMI

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi all, Im using Pylons in combination with WMI module to do some basic system monitoring of a couple of machines, for POSIX based systems everything is simple - for Windows - not so much. Doing a request to the Pylons server to get current CPU, however it's not working well, or atleast with the… >>> More