C-library function- malloc()

Description

The C library function void *malloc(size_t size)allocates the requested memory and returns a pointer to it.

Declaration

Following is the declaration for malloc() function.

void *malloc(size_t size)

Parameters

size -- This is the size of the memory block, in bytes.

Return Value

This function returns a pointer to the allocated memory, or NULL if the request fails.

Example

The following example shows the usage of malloc() function.

#include <stdio.h>
#include <stdlib.h>
int main()
{
char *str;   
/* Initial memory allocation */
str = (char *) malloc(15);
strcpy(str, "tutorialspoint");
printf("String = %s, Address = %u\n", str, str);
/* Reallocating memory */
str = (char *) realloc(str, 25);
strcat(str, ".com");
printf("String = %s, Address = %u\n", str, str);
free(str);
return(0);
}

Let us compile and run the above program that will produce the following result:

String = tutorialspoint, Address = 355090448 String = tutorialspoint.com, Address = 355090448