A pure virtual function is one which must be overridden by any concrete i. We cannot create the instance of an abstract class. We can create pointer and reference of base abstract class points to the instance of the child class. A class is the abstract if it has at least one pure virtual function. Those functions are known as virtual functions. Now coming to an abstract class , it is a kind of class that has at least one pure virtual function is known as abstract class.
USB communications device class
The communications device class is used for computer networking devices akin to a network card , providing an interface for transmitting Ethernet or ATM frames onto some physical media. It is also used for modems , ISDN , fax machines, and telephony applications for performing regular voice calls. This class can be used for industrial equipment such as CNC machinery to allow upgrading from older RS serial controllers and robotics, since they can keep software compatibility. Devices of this class are also implemented in embedded systems such as mobile phones so that a phone may be used as a modem, fax or network port. The data interfaces are generally used to perform bulk data transfer. This computer hardware article is a stub.
Published on February 28, by Shona McCombes. Revised on October 13, An abstract is a short summary of a longer work such as a dissertation or research paper. The abstract concisely reports the aims and outcomes of your research so that readers know exactly what the paper is about. There are four things you need to include:.
Abstraction in C is the process to hide the internal details and showing only the functionality. The abstract modifier indicates the incomplete implementation. The keyword abstract is used before the class or method to declare the class or method as abstract. Also the abstract modifier can be used with indexers , events and properties. An Abstract class is never intended to be instantiated directly.