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()?

Define meaning of call by reference - computer programming, Define the Mean...

Define the Meaning of Call by reference? In "call-by- reference", as an alternative of passing the value of a variable, the location number (or the address) of the variable is

Algorithm, Write a algorithm to explain the processof wakingbup in morning

Write a algorithm to explain the processof wakingbup in morning

Write a Programme that computes the price of portfolio, write a programme t...

write a programme that computes the price of shares and options. do the options in one-period binomial model.

Program, c | c-c-c-c-c | c-c-C-c-c | ...

c | c-c-c-c-c | c-c-C-c-c | c find distance between difftent carbon atom by programing

Loops, how to make a diamond from steric

how to make a diamond from steric

.testvita, answer for tcs is working question

answer for tcs is working question

Coding, I want MODI method''s coding in c++ using all concepts of c++..plea...

I want MODI method''s coding in c++ using all concepts of c++..please help me its my project work...

Program, write a c++ program which finds minimum of three numbers

write a c++ program which finds minimum of three numbers

C program for bubble sort, C program for bubble sort: void main() {...

C program for bubble sort: void main() { int i,j,k,a[10],n; clrscr(); printf("How many values you want to enter\n"); scanf("%d",&n);  for(i=0;i  {  pri

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