NSConnection between an OSX app and a command line tool

Question

I am trying to create a connection between an OSX app and a command line tool to work with distributed objects.

The connection is registered in the command line tool like this

[NSConnection serviceConnectionWithName:@"server" rootObject:extManager];

and an attempt to connect to the registered connection object is made from the app like this

self.serverConnection = [NSConnection connectionWithRegisteredName:@"server" host:nil];

When the app is NOT sandboxed the connection is made. When the app is sandboxed the connectionWithRegisteredName returns nil.

I have tried adding a key and value to the entitlements and signing both the tool and the app with the team certificate but it doesn't work

    <key>com.apple.security.application-groups</key>
    <array>
        <string><TEAM ID>.AppSuite</string>
    </array>

What can I do to make the connection work when sandboxed?

Answer 1

The trick here is to use the app-group name as a prefix in the connection name. ie:

self.serverConnection = [NSConnection connectionWithRegisteredName:@"<TEAM ID>.AppSuite.server" host:nil];

Why?

Mach port names must begin with the application group identifier, followed by a period (.), followed by a name of your choosing.
For example, if your application group's name is Z123456789.com.example.app-group, [...] You might create a Mach port named Z123456789.com.example.app-group.Port_of_Kobe.
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