MacOS - determine the Network Account Server with code - objective-c

Question

I want to detect at runtime of my Mac application (written in Objective-C) if the user's Mac is joined to an Active Directory Server or Open Directory Server and/or any sort of "network account server". And to read the string of that setting if it exists. That is, the the setting from the Login Options pane of the "Users & Groups" applet in Systems Preference. See picture below.
Specifically, just reading the string of the specified server would be sufficient.
What's API set should I be looking at to read this setting?

Answer 1

A computer can be bound to multiple network account servers at one time. To list them you could use the OpenDirectory framework by creating an ODSession and list all registered nodes.
#import <OpenDirectory/OpenDirectory.h>
...
ODSession *mySession = [ODSession defaultSession];
NSError *err;
NSArray *nodeNames = [mySession nodeNamesAndReturnError:&err];
NSLog(#"nodeNames=%#", nodeNames);
I'm bound to Mac-mini.local OpenDirectory Server, and that outputs this:
nodeNames=(
"/Contacts",
"/LDAPv3/Mac-mini.local",
"/Local/Default",
"/Search"
)
To get further information about a registered node, just create an ODNode instance from the node name in the nodeNames array and use that to query that node.
ODNode *node = [[ODNode alloc] initWithSession:mySession name:#"/LDAPv3/Mac-mini.local" error:&err];
Or, you could also create an ODNode instance of a top node, like the /LDAPv3 node, directly and just ask for it's subnodes, like this:
ODNode *node = [[ODNode alloc] initWithSession:mySession name:#"/LDAPv3" error:&error];
NSArray *subnodes = [node subnodeNamesAndReturnError:&err];
NSLog(#"subnodes=%#", subnodes);
That gave me this output:
subnodes=(
"/LDAPv3/Mac-mini.local"
)
Note: there is also -unreachableSubnodeNamesAndReturnError:
If you need more info about this framework, the documentation can be found here