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Dynamic memory allocation in C Language | malloc() function in C Language | free() function in C Language

We can dynamically allocate and de-allocate memory to variables in C language. Different functions for dynamic memory allocation/de-allocation are:

malloc()
free()

1. malloc() function

malloc() is a predefined function of C language that can dynamically allocate memory to variables. It allocates a block of fixed size block from memory. Header file required for malloc() function is stdlib.h.

Example
int *ptr;
ptr=malloc(sizeof(int));

ptr is a pointer that is allocated memory of 2 because sizeof(int) is assumed to return 2 bytes.

Program of malloc().

#include<stdio.h>
#include<stdlib.h>
int main()
{
int *ptr;ptr = malloc(sizeof(int));
*ptr=5;

printf(“*ptr=%d”,*ptr);
free(ptr);
}

Output

*s=15

2. free() function

This function is used to deallocate memory dyanamically assigned to a variable by using malloc() function.

Example:
free(ptr);

This command will dealloacte memory assigned to pointer variable ptr. It has been demonstrated in above program.

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Lesson tags: calloc() function in c, dynamic memory allocation in c, Dynamic memory allocation in C Language, dynamic memory deallocation in c, free() function in c, malloc() function in c, memory leak in c, program of dynamic memory allocation in c, program of dynamic memory deallocation in c

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