I want the SCIP callable to print all messages to stderr (using it as a flatzinc solver). I've tried
SCIP_DECL_MESSAGEWARNING(printMsg) {
cerr << msg << flush;
}
...
SCIP_MESSAGEHDLR* pHndl=0;
SCIP_CALL ( SCIPmessagehdlrCreate ( &pHndl, FALSE, NULL, FALSE, printMsg, printMsg, printMsg, NULL, NULL) );
without effect...