The free() function releases the allocated memory, making it available for malloc() or something else to use.
#include <stdio.h> #include <stdlib.h> int main() /* w w w.ja v a2s . co m*/ { int *age; age = (int *)malloc(sizeof(int)*1); if(age==NULL) { puts("Out of Memory or something!"); exit(1); } printf("How old are you in years? "); scanf("%d",age); *age *= 365; printf("You're over %d days old!\n",*age); free(age); return(0); }