+ /*! take a vector of s4u::ExecPtr and return when one of them is finished.
+ * The return value is the rank of the first finished ExecPtr. */
+ static int wait_any(std::vector<ExecPtr>* execs) { return wait_any_for(execs, -1); }
+ /*! Same as wait_any, but with a timeout. If the timeout occurs, parameter last is returned.*/
+ static int wait_any_for(std::vector<ExecPtr>* execs, double timeout);
+