   Can't I rely to: "!var" instead of "var != NULL" ?
  Hi I have allways checked for null (zero) pointer whit line:if(!pClass)(of course I allways set pClass to zero if example the search function doesn''t find and return the class)But aparently that doesn''t necessary give the right comparison or does it? If not why? 
  if(!pClass) should be fine. ;  If var is a pointer, it works fine. If it is a class, it may not. Niether may work as expected - their behavior is entirely up to the implementer of the class. ;  Yes, you can. ;  Thanks to you all for replys!I just had to be sure on this becose I had earlier heard that it isn''t - well, it happens. 