What is placement new?
Answer / ritesh pal
When you want to call a constructor directly, you use the placement new. Sometimes you have some raw memory that's already been allocated, and you need to construct an object in the memory you have. Operator new's special version placement new allows you to do it.
class Widget
{
public :
Widget(int widgetsize);
...
Widget* Construct_widget_int_buffer(void *buffer,int widgetsize)
{
return new(buffer) Widget(widgetsize);
}
};
This function returns a pointer to a Widget object that's constructed within the buffer passed to the function. Such a function might be useful for applications using shared memory or memory-mapped I/O, because objects in such applications must be placed at specific addresses or in memory allocated by special routines.
| Is This Answer Correct ? | 0 Yes | 0 No |
Discuss about iteration statements in C++ .
Consider the following C++ program
What Are The Differences Between A C++ Struct And C++ Class?
Explain why C++ is not purely Object Oriented Language
What do you by Function Overloading in C++?
0 Answers Akamai Technologies, Infogain,
What are the different scope C++ provide ?
How to run C++ program in cmd
Write a program that ask for user input from 5 to 9 then calculate the average
What is a memory leak in C++?
How to invoke a C function using a C++ program?
Explain function prototypes in C++.
What kind of problems does name mangling cause?