Input(Component &cmp, Connector &con, char *name): In order to build an input port for the runtime component, the Input constructor takes a reference to the component which encloses the input port, a reference to the connector which feeds the input port and a name for the input port. The connector reference and name parameters are passed to the Port base class constructor, thereby connecting the port to its external source connector and storing the name of the port. A connect() message is then sent to the external connector with the component reference as a parameter. This adds the component which encloses the port to the fan-out list of the external connector. The input port is then added to the input port list of the enclosing component.
void send_signal(Signal sig): This method overrides the corresponding virtual function in the Port class. Because input ports cannot send signals, this function simply displays an error message indicating that an input port attempted to generate a signal.