char    *my_strcat(char *dest, const char *src)
{
  int new_length; = my_strlen(src) + my_strlen(dest) + 1;

  char *result = realloc(dest, new_length);
  dest += dest_len;
  while(*src != 0)
    {
        dest = *src;
        dest++;
        src++;
    }
  *dest = 0;

  return result;
}