[Scip] How to access a subscip in ObjPricer::scip_redcost?

[Sebastian Ruther]

  Hello,

I'm implementing a Branch-and-Price algorithm. In the examples the 
variables are always generated by the subscip which is generated in the 
ObjPricer::scip_redcost call. However, I don't want to generate the 
subscip problem in every iteration so I generate my subscip in 
ObjPricer::initsol by calling
SCIP*      subscip = NULL;
SCIP_CALL( SCIPcreate(&subscip) );
SCIP_CALL( SCIPincludeDefaultPlugins(subscip) );
SCIP_CALL( SCIPcreateProb(subscip, PricingNameBuf.str().c_str(), 0, 0, 
0, 0, 0, 0, 0) );

How do I access the SCIP* subscip in the ObjPricer::scip_redcost 
function? The parameter list only gives me the SCIP* scip which refers 
to the master problem.

Thanks
Sebastian