Isn't DDE all asynchronous anyway?

The Old New Thing : Please feel free to stop using DDE

The Old New Thing : Please feel free to stop using DDE — Mon, 26 Feb 2007 18:49:54 GMT

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re: Isn't DDE all asynchronous anyway?

DS Guy — Thu, 28 Sep 2006 00:16:01 GMT

What about the environment variable SRDDE that is mentioned here?

http://www.geocities.com/~budallen/errors.html

It appears this makes DDE synchronous if you're using DDEML.DLL

re: Isn't DDE all asynchronous anyway?

Magnus — Wed, 27 Sep 2006 17:52:22 GMT

The MSDN page linked to with "interprets DDE-based file associations " is a bit out of date and should be updated, it says nothing about per user registered verbs.

re: Isn't DDE all asynchronous anyway?

Carlos — Wed, 27 Sep 2006 17:36:32 GMT

"As an application programmer, can I really ignore DDE if I need to interact with explorer/shell?"

If you're targetting Windows XP onwards you can use IDropTarget:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/shellcc/platform/shell/programmersguide/shell_basics/shell_basics_extending/fileassociations/fa_verbs.asp

re: Isn't DDE all asynchronous anyway?

Chris Becke — Wed, 27 Sep 2006 10:40:51 GMT

@Christian: If you want to make your computer more responsive, find and eliminate the apps that dont respond to broadcast windows messages quickly.

re: Isn't DDE all asynchronous anyway?

Brian — Wed, 27 Sep 2006 03:05:31 GMT

I doubt that would make your computer any more responsive. Applications have quite a bit of overhead involved in launching, much more than the overhead involved in DDE.

re: Isn't DDE all asynchronous anyway?

Christian — Tue, 26 Sep 2006 23:50:07 GMT

I hate DDE. I wished all programms just launch by looking up the file-association and starting that programm. If the programm launches an second instance: GREAT! I just want that.
If the programm has some kind of fear of running twice: It shall take care of that problem itself and find it's existing process and transfer execution to it.
Not that it can do anything against that happening anyway.

Wouldn't it be possible to create a tool that walks through the registry and exchanges all the DDE-stuff with just launching the EXE-file and passing the data file as first command line parameter?

I feel this would make my computer much more responsive!

re: Isn't DDE all asynchronous anyway?

Frederic Merizen — Tue, 26 Sep 2006 21:38:21 GMT

Ben, read this and be enlightened:

http://blogs.msdn.com/oldnewthing/archive/2006/06/21/641456.aspx

re: Isn't DDE all asynchronous anyway?

Ben Cooke — Tue, 26 Sep 2006 20:01:20 GMT

I'm sure there's somewhere I could look up the answer to this, but I admit it: I'm lazy.

After the shell has launched the application that provides the DDE server, how does it know when that app is ready to respond to the DDE broadcast? Does it just keep sending out WM_DDE_INITIATE every n seconds until something answers? What if it's misconfigured and the launched app doesn't provide a DDE server at all?

(As you can probably tell, I managed to avoid ever learning about DDE!)

re: Isn't DDE all asynchronous anyway?

DDE: old or new? — Tue, 26 Sep 2006 18:57:25 GMT

As an application programmer, can I really ignore DDE if I need to interact with explorer/shell?