What is copy constructor C++?

A user-defined copy constructor is generally needed when an object owns pointers or non-shareable references , such as to a file, in which case a destructor and an assignment operator should also be written (see Rule of three).

Copy constructor is called when a new object is created from an existing object, as a copy of the existing object . Assignment operator is called when an already initialized object is assigned a new value from another existing object.28 Haz 2021

The copy constructor is a constructor which creates an object by initializing it with an object of the same class, which has been created previously . The copy constructor is used to − Initialize one object from another of the same type. Copy an object to pass it as an argument to a function.