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.

When would you choose to return an error code rather than throw an exception?

0 Answers   Amazon,

---

Explain the operator overloading feature in C++ ?

0 Answers  

---

What is RTTI and why do you need it?

0 Answers   Amazon,

---

Write a C++ Program to Display Number (Entered by the User).

1 Answers  

---

How will you print a list of all unique words from a string which may contain repeated words?

0 Answers   Adobe,

---

What are "pure virtual" functions?

0 Answers   Adobe, Alter, iNautix,

---

What are the advantages and disadvantages of B-star trees over Binary trees?

0 Answers  

---

Tell How To Check Whether A Linked List Is Circular ?

1 Answers   IBS, Infosys,

---

What is constant keyword in C++? Illustrate its various uses.

0 Answers   Akamai Technologies, Infogain,

---

Name the operators that cannot be overloaded.

1 Answers   Wipro,

---

What are Agilent PRECOMPILERS?

0 Answers   Agilent,

---

Define namespace.

1 Answers  

---