Do i have to check for null after p = new fred()?, C/C++ Programming

Assignment Help:

A: No. (Excluding if you have an old compiler, you might have to force the new operator to throw an exception if it runs out of memory.)

This turns out to be a real pain to always write down explicit NULL tests after each new allocation. Code like the following is extremely tedious:

Fred* p = new Fred();

if (p == NULL)

throw std::bad_alloc();

If your compiler doesn't support (or if you reject to use) exceptions, your code may be even more tedious:

Fred* p = new Fred();

if (p == NULL) {

std::cerr << "Couldn't allocate memory for Fred" << std::endl;

abort();

}

In C++, if the runtime system can't allocate sizeof(Fred) bytes of memory throughout p

= new Fred(), a std::bad_alloc exception will thrown. Unlike malloc(), new never returns

NULL!

Then you should simply write:

Fred* p = new Fred(); // No require to check if p is NULL

Though, if your compiler is old, it might not yet support this. Determine by checking your compiler's documentation under "new". If you hold an old compiler, you might have to force the compiler to have this behavior.

 

Note: If you are using Microsoft Visual C++, to obtain new to throw an exception while it fails you have to #include some standard header in at least one of your .cpp files. For instance, you could

#include (or or or ...).

 

 


Related Discussions:- Do i have to check for null after p = new fred()?

What do you mean by a sequential access file, What do you mean by a sequent...

What do you mean by a sequential access file? - When writing programs which store and retrieve data in a file, it's possible to designate that file into various forms. - A s

Explain object-oriented programming, Explain Object-oriented programming ...

Explain Object-oriented programming Object-oriented programming (OOP) attempts to meet these requirements, providing methods for managing enormous complexity, achieving reuse o

Develop g-code generating software, Develop G-code generating software P...

Develop G-code generating software Project Description: I'm presently using Slicer on a polymer jetting 3d printer. The toolpaths were thought out for FDM printers and thus a

PEBBLE MERCHANT, C CODE FOR PEBBLE MERCHANTS PROBLEM

C CODE FOR PEBBLE MERCHANTS PROBLEM

Sums a sequence of integers, assume that the first integer read with cin sp...

assume that the first integer read with cin specifies the number of values remaining to be entered. that program should read only one value each time cin is executed .a typical inp

Write a c program to input five numbers, Write a C program to input five nu...

Write a C program to input five numbers and print them out on a new line e.g 5, 10, 15, 20, 25 displayed as   5   10   15   20   25 #include stdio.h   void main()   {

I need script for auto seating poker, Project Description: Not just like...

Project Description: Not just like that though. I want a similar program that can scan through poker lobbys (pokerstars, full tilt, ongame and ipoker) and seat me to the left of

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd