title: How do I free memory obtained by sbrk()?
body: <p>I have a custom allocator function which uses sbrk() to obtain memory.
  How do I release this memory when it's no longer needed?</p>
  
  <p>Is there a function equivalent to free() for malloc() ?</p>
  
  <p>or do I have to use brk() to set the end of the data segment ?</p>