The difference between new and malloc in c++

The difference between new and malloc: new is a type-safe C operator, used to create objects of a specified type and return a pointer to the object. malloc is a C standard library function that allocates an untyped block of memory and returns a void* pointer to the memory block. new calls constructors and destructors, malloc does not. new manages memory by the C runtime, while malloc requires manual management.

The difference between new and malloc in C

In C, new and malloc are all functions used for dynamic memory allocation. However, there are some key differences between them:

1. Syntax and return types:

• new is a C operator that creates a new object of a specified type and returns a pointer to that object.
• malloc is a C standard library function that allocates a memory block of a specified size and returns a void* pointer to the memory block.

2. Type Safety:

• new is type safe because it will Check types match when allocating memory. For example, int* p = new int; allocates an integer pointer, while p = malloc(sizeof(int)); only allocates a block of memory without type checking.
• malloc is not type-safe, it only allocates memory, and the caller is responsible for managing the type of the object.

3. Construction and destruction:

• ##new The constructor of the object will be called first. Then returns a pointer to the object. When an object goes out of scope, its destructor is automatically called.
• malloc Will not call the constructor or destructor. These functions need to be managed manually by the caller.

4. Memory Management:

• new Memory management is handled by the C runtime. It maintains an internal heap in the background and is responsible for allocating and freeing memory.
• malloc Requires manual memory management. The caller is responsible for allocating, freeing, and reallocating memory. Improper memory management can cause memory leaks or segfaults.

Summary:

• new is a type-safe operator in C for creating new objects.
• malloc is a C standard library function used to allocate untyped raw memory.
For dynamic memory allocation,
• new is generally the safer and preferable choice in C programs.

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