The Moth

If you have .NET apps talking to each other on the same machine today, chances are you are using remoting. Furthermore, you are probably using binary over tcp and have dealt with the idiosyncrancies of handling events over remoting.

So what is new with .NET 2.0 for this scenario? Well, there is now an Ipc namespace, and using it offers performance improvements over the TCP one. To use it you need to change your config files (and of course you are using config files and not setting up the channel programmatically :-).

Assuming your server.exe.config file looks like this, you simply have to change it to look like this:

<?xml version="1.0" encoding="utf-8" ?>

<configuration>

    <system.runtime.remoting>

	<application name="ServerHost">

	    <service>

		<activated type="SomeNamespace.SomeClass, SomeDllName" />

	    </service>

	    <channels>

		<channel ref="ipc" portName="server">

		    <serverProviders> 

			<formatter ref="binary" typeFilterLevel="Full" /> 

		    </serverProviders>

		</channel>

	    </channels>

	</application>

    </system.runtime.remoting>

</configuration>

Assuming your corresponding client.exe.config looks like this, you have to change it to look like this:

<?xml version="1.0" encoding="utf-8" ?>

<configuration>

    <system.runtime.remoting>

	<application>

	    <client url="ipc://server/ServerHost">

		<activated type="SomeNamespace.SomeClass, SomeDllName" />

	    </client>

	    <channels>

	        <channel ref="ipc" portName="client">

		    <serverProviders> 

			<formatter ref="binary" typeFilterLevel="Full" /> 

		    </serverProviders>

		</channel>

	    </channels>

	</application>

    </system.runtime.remoting> 

</configuration>

The changes may seem obvious (isn't everything once you know it:-), but I would not have figured the above out if it wasn't for Manish G, whose help was invaluable.

Another improvement with .NET 2.0 – well with the IDE really – is the ability to add references to EXE assemblies, not just DLLs. You can do this today via the command line, but with VS2005 you can do it in the IDE as well. This brings us closer to the ActiveX EXE days (out-of-proc COM) where there were only two files. So you can now merge (if that is what your design wishes) SomDllName.dll into the Server.exe and offer the SomeNamespace.SomeClass from it directly.

That's it!

UPDATE: On Ohad's WebLog you can see how to use IPC programmatically