Enumerating possible production chains

The following code shows how to fine control the enumeration process. It enumerates Production Chains for producing User output, reducing the options using a basic query, and then chooses the first one from all possibilities.

// Build a query object
xn::Query query;
nRetVal = query.SetVendor("MyVendor");
// TODO: check error code

query.AddSupportedCapability(XN_CAPABILITY_SKELETON);
// TODO: check error code

// Enumerate
xn::NodeInfoList possibleChains;
nRetVal = context.EnumerateProductionTrees(XN_NODE_TYPE_USER, &query, possibleChains, NULL);
// TODO: check error code

// No errors so far. This means list has at least one item. Take the first one
xn::NodeInfo selected = *possibleChains.Begin();

// Create it
nRetVal = context.CreateProductionTree(selected);
// TODO: check error code

// Take the node
xn::UserGenerator userGen;
nRetVal = selected.GetInstance(userGen);
// TODO: check error code

// Now we can start to use it