C

C Syntax of realloc()

ptr = realloc(ptr, x);

realloc in c

#include <stdio.h>
int main () {
   char *ptr;
   ptr = (char *) malloc(10);
   strcpy(ptr, "Programming");
   printf(" %s,  Address = %u
", ptr, ptr);

   ptr = (char *) realloc(ptr, 20); //ptr is reallocated with new size
   strcat(ptr, " In 'C'");
   printf(" %s,  Address = %u
", ptr, ptr);
   free(ptr);
   return 0;
} 

realloc in c

void *realloc(void *ptr, size_t size)

Realloc in C language

#include <stdio.h>
#include <stdlib.h>
int main()
{
int *ptr = (int *)malloc(sizeof(int)*2);
int i;
int *ptr_new;
	
*ptr = 10;
*(ptr + 1) = 20;
	
ptr_new = (int *)realloc(ptr, sizeof(int)*3);
*(ptr_new + 2) = 30;
for(i = 0; i < 3; i++)
	printf("%d ", *(ptr_new + i));

getchar();
return 0;
}