MemAvail                 Returns Total Amount of Memory Available

 MemAvail : Integer;

    Returns the total amount of memory available for allocation in the
    heap. The value returned is in paragraphs (16-byte chunks).

          Notes:    If the value returned is less than 0, the actual
                    amount of memory is equal to 65536.0 + MemAvail.

                    In order to get the size in bytes, multiply the value
                    returned by 16.0 and assign this result to a real
                    variable (to avoid overflow).

  -------------------------------- Example ---------------------------------

           var
             Biggest : Real;

           { Compute the total amount of memory available }
           if MemAvail < 0 then
             Biggest := 16.0 * (65536.0 + MemAvail)
           else
             Biggest := 16.0 * MemAvail;