1) malloc() and calloc() return void * type and this allows these functions to be used to allocate memory of any data type (just because of void *). We can't do arithmetic operation on void* pointer as it doesn't have information regarding the underlying object type. What will be the output of the following C++ code? 1) void pointers cannot be dereferenced. For example the following program doesn’t compile. c) double View Answer. They can be a beginner, fresher, engineering graduate or an experienced IT professional. November 9, 2018 Creating Expressive C++ Smart Pointers for Remote Memory. Answer: a Explanation: Because the void pointer is used to cast the variables only, So pointer arithmetic can’t be done in a void pointer. c) memory address a) abcdefghij When does the void pointer can be dereferenced? d) static Im not sure how to do this. View Answer. View Answer, 4. pointer arithemetic pointer functions both of the mentioned none of the mentioned. It is pretty much a similar situation with dereferencing a void pointer. d) pointer functions & objects d) runtime error b) no output By using our site, you View Answer. d) 12 View Answer, 3. Void pointer is a specific pointer type – void * – a pointer that points to some data location in storage, which doesn’t have any specific type. d) runtime error Types, Pointers, Arrays & Structures in C++, Functions, Namespaces & Exceptions in C++, Source Files, Classes & Operator Overloading in C++, Derived Classes, Templates & Exception Handling in C++, Prev - C++ Programming Questions and Answers – References – 3, Next - C++ Programming Questions and Answers – Structures, C++ Programming Questions and Answers – References – 3, C++ Programming Questions and Answers – Structures, C Algorithms, Problems & Programming Examples, Dynamic Programming Problems and Solutions, C Programming Examples on Numerical Problems & Algorithms, C Programming Examples on Data-Structures, Java Programming Examples on Multithreading, Java Programming Examples on Exception Handling, Object Oriented Programming Questions and Answers. close, link It points to some data location in the storage means points to the address of variables. It can be reused to point at any data type we want to. pointer functions. Some Interesting Facts: a) equal Would be better off providing overloaded functions for each type of parameter that can be accepted. Recommended Articles. Answers: pointer arithemetic. There is no way the compiler can know (or guess?) Void refers to the type. View Answer. Attention reader! Instead what is exchanged are pointers to values. They cannot be directly dereferenced. Void Pointer. View Answer. Note that the above program may not work in other compilers. 2) The C standard doesn’t allow pointer arithmetic with void pointers. All Rights Reserved. All pointers, regardless of pointee, are 8-byte addresses that are type-compatible with void*. c) pointer objects A directory of Objective Type Questions covering all the Computer Science subjects. View Answer. a) pointer arithmetic b) pointer functions c) pointer objects d) pointer functions & objects View Answer. Finally, void pointers. What we can’t do on a void pointer? what type of data is pointed to by the void pointer. It is declared like this: void *pointerVariableName = NULL; Since they are very general in nature, they are also known as generic pointers. Passing by pointer Vs Passing by Reference in C++, Data Structures and Algorithms – Self Paced Course, Ad-Free Experience – GeeksforGeeks Premium, We use cookies to ensure you have the best browsing experience on our website. Void pointers do one thing and one thing only: store an address. Dereferencing a void Pointer # We can't just dereference a void pointer using indirection ( * ) operator. While we can certainly specify parameters that are void * parameters, we cannot dereference a void pointer without knowing the data type to which it points. In my work as a graduate student, I build distributed data structures, and having a remote pointer abstraction is an essential tool for me to write clean, correct code. One shall practice these questions to improve their C++ programming skills needed for various interviews (campus interviews, walk-in interviews, company interviews), placements, entrance exams and other competitive exams. Basically the type of data that it points to is can be any. c) using delete keyword d) none of the mentioned This is because a void pointer has no data type that creates a problem for the compiler to predict the size of the pointed object. 2) void pointers in C are used to implement generic functions in C. For example compare function which is used in qsort(). I'm still think about some safe conversion of that pointers and wrote little code that make some conversions using void pointer and return void from function. b) 6 A generic pointer can be assigned a pointer value of any type, but it may not be dereferenced. then is static_cast conversion to needed format. Experience. Since we cannot dereference a void pointer, we cannot use *ptr.. b) class member in c++ The content of pointer is 2.3. Object Oriented Programming Using C++ Objective type Questions and Answers. Ben's Blog Blog Index Personal Website. 8. c) both const & volatile Void pointers are useful when you … Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Learning Series – C++ programming questions and answers focuses on “ pointer to another type. C++ Objective type questions and answers used to point at any data we... To which type of parameter that can be typcasted to any type all the important DSA concepts the... Part of the following C++ code no way the compiler to dereference the thing on right. Declared with which of these of C++ concepts size of void is 1 other.. We must explicitly typecast return value of the mentioned none of the following C++ code a similar with! Is a pointer as mod_req ( Func < int > ) void * void (. 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