Sion Semiconductors Interview Questions and Answers

Runtime polymorphism in C++ is achieved through virtual functions, vptr (virtual pointer), and vtable (virtual table).

• Runtime polymorphism allows objects of different classes to be treated as objects of a common superclass.

• Virtual functions are declared in a base class and overridden in derived classes to achieve polymorphism.

• vptr is a pointer that points to the vtable of an object, allowing dynamic binding of virtual ...read more

I primarily use C++17, but I am familiar with earlier versions as well.

• I am comfortable working with features introduced in C++17 such as structured bindings and constexpr if

• I have experience with earlier versions like C++11 and C++14

• I stay updated with the latest features and improvements in C++ standards

Yes, I have used Windows API's extensively in my previous projects.

• I have used Windows API's for tasks such as creating windows, handling messages, and interacting with system resources.

• Examples include using functions like CreateWindow, SendMessage, and ReadFile.

• I have also worked with specific Windows API's like Winsock for networking and WinINet for internet-related tasks.

dynamic_cast is a C++ operator used for safe downcasting of pointers and references in polymorphic classes.

• dynamic_cast is used to safely downcast a pointer or reference from a base class to a derived class.

• It can fail if the object being casted is not of the target type, in which case it returns a null pointer for pointers or throws a std::bad_cast exception for references.

• Dynamic_cast can only be used with pointers o...read more

Union in C++ is a data structure that allows storing different data types in the same memory location.

• Unions are similar to structures but all members share the same memory location.

• Only one member of a union can be accessed at a time.

• Unions are useful when you need to store different data types in the same memory space.

• Example: union MyUnion { int i; float f; };

• Example: MyUnion u; u.i = 10; // Accessing integer member

Weak pointer is a type of smart pointer in C++ that does not control the lifetime of the object it points to.

• Weak pointers are used to break circular references in shared pointers.

• They do not increase the reference count of the object.

• They are used in scenarios where the object may be deleted while there are still weak pointers pointing to it.

Processes and threads are units of execution in a computer system. Memory is allocated to processes. Mutex and semaphore are synchronization mechanisms. Core refers to a processing unit in a multi-core system. Context switching is the process of switching between different processes or threads.

• Processes are independent units of execution with their own memory space and resources.

• Threads are lightweight units of executi...read more