vvvv

• Sep 16th, 2005

 

The dynamic objects will be created in a pre-allocated heap memory.Accordingly the destructor of each class will call explicitly.

sivakumar.v

 Profile Answers by sivakumar.v 

• Jul 3rd, 2008

 

Placement new is supported in C++.  As such 'placement new' is an extension to new operator and its usage.   Well, will go through by giving an example.  In embedded systems, memory is very critical (or), any time critical application should not get into memory related problems.

Usually, developers will create memory pools, so that all the memory allocated in the application should be from this memory pool only. 


Ex : char *myMemPool = new char[10000]; // it allocates 10000 bytes of memory.

Now, I am creating one class object, which takes some 500 bytes of data + some functions e t c.

class A *aObject = new (myMemPool) A("I am the data to A"); // this is placement new allocates memory from memory pool .

class A *bObject = new A("I am no special");  // ordinary heap allocation

Cheers.
/Siva

vsvraju

 Profile Answers by vsvraju 

• Aug 8th, 2008

 

With the help of placement new, one can place the object at his desired (specified) location.

vidhudatta

 Profile Answers by vidhudatta 

• Sep 23rd, 2009

 

Placement syntax allows programmers to explicitly specify memory management of objects. The placement versions of new operator is called placement new.

sachin_mundhra

 Profile Answers by sachin_mundhra 

• Dec 18th, 2009

 

Using placement new operator user can allocate memory in a specific memory address.

Example:
SomeClass at a particular memory address stored in a pointer type variable named pmem
new(pmem) SomeClass;