What's the Difference Between the `new` Operator and `operator new` in C ?

Distinguishing "new Operator" from "Operator new"

In C , understanding the difference between the "new operator" and "operator new" is crucial. While both concepts involve memory allocation, they serve distinct purposes.

Operator new

Operator new is a function that allocates raw memory space. It functions similarly to malloc(), providing an untyped memory block. You can directly call operator new, but it's uncommon unless you're developing low-level memory management components. The syntax is:

char *x = static_cast<char *>(operator new(100));

Additionally, operator new can be overloaded globally or for specific classes. Its signature is:

void *operator new(size_t);

New Operator

In contrast, the "new operator" is employed to create objects dynamically. It utilizes operator new to allocate memory and subsequently calls the constructor for the corresponding object type. This results in an initialized object in the allocated memory, including any embedded objects or base class constructors. The syntax is:

my_class *x = new my_class(0);

Key Difference

The primary distinction lies in the scope and purpose of these concepts. While operator new merely allocates raw memory, the new operator allocates memory and initializes an object using the specified constructor.

Conclusion

Familiarity with the differences between "new operator" and "operator new" is essential for effective memory management in C . Understanding their distinct roles and applications enables you to optimize your code performance and avoid resource-related issues.

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