hi, my apologies for the incomplete post. yes p will not be NULL but have a value, but that's not the prob. the code in question is p = &root->child; for (;;) { >> tmp = *p; << if (!tmp || tmp->start > end) { ... ... the line "tmp = *p" essentially translates to "tmp = *&root->child" or "tmp = root->child"....so i think tmp will have a NULL val. then won't the "if" condition where tmp's member is being accessed "tmp->start" give a prob. (null pointer derefernce)??? On Thu, 2004-10-07 at 16:43, Thekkedath, Gopakumar wrote: > >struct resource *tmp, **p; > ... > >p = &root->child; > > >child member of root is NULL right??? cos it was'nt initialized > >to any specfic val (so it wud have the default val. of NULL). > > > As this is > &root->child and not > root->child, 'p' wont be NULL but the address of child -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/