Vtable Vpointers Virtual Functions Runtime Polymorphism The M Finally starting the #c series, this series is for c specific interviews and these are very common questions asked in many companies like intuit, adobe,. From "virtual functions in c ": whenever a program has a virtual function declared, a v table is constructed for the class. the v table consists of addresses to the virtual functions for classes that contain one or more virtual functions. the object of the class containing the virtual function contains a virtual pointer that points to the.
Virtual Functions And Runtime Polymorphism In C Set 1 Introduction The vtable, or virtual table, is a table of function pointers that is created by the compiler to support dynamic polymorphism. whenever a class contains a virtual function, the compiler creates a vtable for that class. each object of the class is then provided with a hidden pointer to this table, known as vptr. A virtual function is a member function that is declared in the base class using the keyword virtual and is re defined (overridden) in the derived class. it tells the compiler to perform late binding where the compiler matches the object with the right called function and executes it during the runtime. this technique falls under runtime. The virtual table is a lookup table of functions used to resolve function calls in a dynamic late binding manner. the virtual table sometimes goes by other names, such as “vtable”, “virtual function table”, “virtual method table”, or “dispatch table”. in c , virtual function resolution is sometimes called dynamic dispatch. C effectively supports three types of polymorphism: function overload (compile time) templates (compile time) virtual functions (runtime) virtual functions allows for late binding of function calls based on object type. it comes into play when a derived object is addressed via a pointer or a reference to a base class.
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