On Sat, 9 Oct 2004 18:22:47 +0100 (BST), Dinesh Ahuja <mdlinux7@xxxxxxxxxxx> wrote: > Hi Simith > > > [Simith] Memsetting to 0 is initialising "next" to > > NULL. > > That is fine that we are memsetting it to NULL, but > what is a significance of this data member if we are > allocating the memory with kmalloc to scull_devices. I was going to be the pedant that pointed out the NULL initialization earlier, but thought I'd wait in case someone who's recently read LDD could shed some further light. Since that's not happened, here goes... > As such I am not able to understand the logic behind > using next data member in the Scull_Device structure. If my memory serves me correct, they like to give a lot of compsci style overblown examples which don't necessarily have a practical purpose - so for example I think the situation you are referring to is one where they allocate a large block of memory to serve as an example backing store and then do some data structure maniupulation within it with the linked lists just so you can see the kind of activity which might take place. I'm not criticising their approach (it would be nice if all theory taught today was as fun - my OS courses at University had such potential, but didn't go anywhere, mostly due to the lack of understanding of the students) but read it from the pragmatic viewpoint of learning, not getting practical implementation. Cheers, Jon. -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
