A C program showing the structure of address spaces

address_spaces.c

#include <stdio.h>
#include <stdlib.h>

int main() {
  printf("location of Code: %p\n", (void *) main);
  printf("location of Heap: %p\n", malloc(1));
  int x = 10;
  printf("location of Stack: %p\n", &x);
  return 0;
}

structure.md

The following depicts the structure of a typical address space

  +-------------------------------------+
  |             Program Code            |
  +-------------------------------------+
  |                 Heap                |   Grown downwards
  +-------------------------------------+   vvvvvvvvvvvvvvv
  |                  ^                  |
  |                  |                  |
  |                  |                  |
  |                  |                  |
  |                  |                  |
  |                  |                  |
  |              Free Space             |
  |                  |                  |
  |                  |                  |
  |                  |                  |
  |                  |                  |
  |                  v                  |
  +-------------------------------------+   ^^^^^^^^^^^^^
  |                Stack                |   Grows upwards
  +-------------------------------------+

The output of the program is

location of code: 0x400517
location of heap: 0x19fd420
location of stack: 0x7ffdb3390134

Which is consistent with the order of these locations as depicted in the diagram