Difference-Detween-Malloc-And-Calloc-In-C
INTRODUCTION
The dynamic memory allocation functions in C are malloc and calloc. They both accomplish the same things, but initialize the memory that has been allocated differently. The distinctions between calloc and malloc are described below:
1. Purpose
malloc: To allocate a block of bytes of memory, use the malloc function. It asks for how many bytes to allocate as a parameter and then returns a reference to the start of the memory block that was allotted. The allocated memory's initial contents are empty.
calloc: Using the calloc function, you can allocate a block of memory and then set its initial value to 0. The number of elements to distribute and the dimension of every component are the two arguments. These two inputs are multiplied to determine the total amount of memory allocated, and a reference to the start of the memory block allocated is returned.
2. Initialization
malloc: The memory assigned by malloc has garbage values, indicating that the memory's initial content is undefinable. The programmer is in charge of explicitly initializing the memory before utilizing it, if necessary.
calloc: Calloc automatically initializes all bits in the memory it allots to zero. This initialization is helpful for initializing arrays or structures since it makes sure that every memory location is assigned to a known state.
3. Performance:
malloc: Malloc can be a little bit quicker than calloc because it doesn't initialize the memory that is allocated.
calloc: Calloc may be a little slower than malloc since it initializes the memory that has been allocated to zero. However, until a significant amount of RAM is being allocated, the speed difference is typically insignificant.
4. Usage:
malloc: When allocating space for dynamic arrays, buffers, or objects when explicit initialization is not necessary, malloc is frequently used.
calloc: When allocating space for arrays or structures that must be initialized to zero or when handling data that needs to be initialized to zero before use, calloc is often employed.
5. Error Handling:
Both malloc and calloc can return a NULL pointer if the memory allocation fails. It's important to check the return value to handle such situations properly.
Example using malloc
#include <stdio.h>
#include <stdlib.h>
int main() {
int* numbers;
int size, i;
printf("Enter the size of the array: ");
scanf("%d", &size);
numbers = (int*)malloc(size * sizeof(int));
if (numbers == NULL) {
printf("Memory allocation failed!");
return 1;
}
printf("Uninitialized values:\n");
for (i = 0; i < size; i++) {
printf("%d\n", numbers[i]);
}
free(numbers);
return 0;
}
OUTPUT
![DIFFERENCE BETWEEN MALLOC AND CALLOC IN C](https://static.tutorialandexample.com/c/difference-between-malloc-and-calloc-in-c1.png)
Example using calloc
#include <stdio.h>
#include <stdlib.h>
int main() {
int* numbers;
int size, i;
printf("Enter the size of the array: ");
scanf("%d", &size);
numbers = (int*)calloc(size, sizeof(int));
if (numbers == NULL) {
printf("Memory allocation failed!");
return 1;
}
printf("Initialized values:\n");
for (i = 0; i < size; i++) {
printf("%d\n", numbers[i]);
}
free(numbers);
return 0;
}
OUTPUT
![DIFFERENCE BETWEEN MALLOC AND CALLOC IN C](https://static.tutorialandexample.com/c/difference-between-malloc-and-calloc-in-c2.png)
Differences between malloc and calloc
malloc | calloc | |
Arguments | Takes the no of bytes to allocate | Takes the no of elements and the size of each element |
Initialization | Memory is uninitialized and contains garbage values | Memory is automatically initialized to zero |
Performance | Slightly faster as it doesn’t perform initialization | Slightly slower due to initialization step |
Usage | Commonly used when explicit initialization is not required | Used when memory needs to be initialized to 0 or when working with arrays |
Purpose | Allocates a block of memory in bytes | Allocates and initializes a block of memory |
Conclusion
malloc and calloc functions are used to allocate dynamic memory, but they behave differently when it comes to initializing the memory that has been allocated. Uninitialized memory is provided by malloc, which provides flexibility and efficiency. When initialization is optional or will be done independently, it is appropriate. To prevent unpredictable behaviour, the developer must explicitly initialize the memory. Calloc, on the other hand, immediately sets the allocated memory to 0. This makes it simple to initialise arrays or structures because it guarantees that every memory location is initialised to a known state. It decreases the need for additional coding and lowers the likelihood of memory-related errors being introduced. Malloc can be a good option due to its effectiveness and versatility if initialization is optional or will be carried out independently. When working with arrays or structures or if automatic zero initialization is requested, calloc offers the ease of automatically initializing the memory.