On Mon, Jul 11, 2011 at 1:43 PM, StephanT <stman937-linewbie@xxxxxxxxx> wrote: > Hi all, > > ----- Original Message ----- >> From: Greg Freemyer <greg.freemyer@xxxxxxxxx> > > >> >> Correct, ioctl is no longer preferred, but it is definitely still >> used. And the ext4 team is still adding new ioctl commands despite it >> being discouraged. >> > > > If ioctl is no longer preferred what is its preferred alternative ? For simple tasks related to processes procfs. (I think procfs is read only from user space) For simple tasks related to devices sysfs (sysfs is read / write from userspace, but uses very simple data formats. No structures as an example. For complex controls, netlink sockets: http://www.linuxjournal.com/article/7356 is a 5 year article I found with a quick grep. > Could you, please explain why ioctl felt in disgrace. I really don't recall the details, but I'm almost positive I've seen new patches rejected because they were based on ioctl's. Can someone else please confirm I'm not imagining things. As I recall, it has to do with the various architectures not being easily handled by the ioctl ABI. ==> Here's one quote I just found from lkml Feb. 2010 Can you describe what your driver is doing? One rule of thumb is that if you already require a character device, using ioctl is the right answer, but you shouldn't create a character device if all you want to do over it is a single ioctl operation. Arnd === Greg _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
