If I use the SOAP syntax, in a consult context of a Company you can use
<datacontainer operation="Acti"> to retrieve the dataset of linked actions.
Generally speaking, in a consult context, with an empty operation or operation="master" you get the main dataset of the consult, with operation="detail" you get the Detail dataset.
Mutatis mutandis for the JSON RPC.
Of course, this is exactly the same as running the query with the appropriate (master, detail) in the database.