Check if a user is a local or domain account - c++

Question

Given the name of a user in OS X, it is possible to query its Active Directory SID using the BSD membership functions.
However, when a local user name is provided on a machine that is not a member of a directory, an SID is also returned.
A solution for checking if the local logged-in user is a domain account is provided here, but this assumes that the user in question is that of the current session, which may not be the case. In addition, if the user is a mobile account (roaming), then a home directory is found and it returns incorrectly.
So, how would one check if a given username is a local or domain user where the username can be any name, including names used for local processes?

Answer 1

Using OpenDirectory API I've managed to achieve a similar task, here is the modified solution that would fit your query:
bool isDomainUser(std::string currentUser)
{
NSString *queryVal = [NSString stringWithUTF8String:currentUser.c_str()];
ODSession *session = [ODSession defaultSession];
ODNode *node = [ODNode nodeWithSession:session
type:kODNodeTypeAuthentication error:NULL];
ODQuery *query = [ODQuery queryWithNode:node forRecordTypes:kODRecordTypeUsers
attribute:kODAttributeTypeRecordName
matchType:kODMatchEqualTo
queryValues:queryVal
returnAttributes:kODAttributeTypeStandardOnly
maximumResults:0 error:NULL];
NSArray *records = [query resultsAllowingPartial:NO error:NULL];
for (ODRecord *record in records)
{
ODAttributeType type = #"dsAttrTypeStandard:OriginalAuthenticationAuthority";
NSArray *lines = [record valuesForAttribute:type error:nil];
if (lines)
{
for(NSString *line in lines)
{
if ([line hasPrefix:#"NetLogon"])
{
return true;
}
}
}
}
return false;
}