Hi, With 2.6.15 and above, when a new device is added (or removed) the kernel driver subsystem sends a uevnt to user space (BTW, these are not the only cases where a uevent message is sent from the kernel; such a message is also sent when there is a repartitioning of a disk , as in sfdisk -R , and when there is a switch of console mode.).
The user space udevd damon listens and gets this message (which is sent over a NETLINK socket). It sees if there is a matching rule, and in case there is, the module is loaded (or removed when the device is removed). For further details you can look in lib/kobject_uevet.c , in kobject_uevent() method. Regards, Rami Rosen On 8/2/06, Ilya Konstantinov <[EMAIL PROTECTED]> wrote:
Rami Rosen wrote: > Hi, > One little remark: > The use of hotplug is now deprecated from kernel version 2.6.15 on. > See for example , http://lwn.net/Articles/166954 This is confusing: From what I gather, udev traditionally does its work when the kernel module is loaded and the device is already known (e.g. KERNEL="hda[a-z]"). On the other hand, hotplug does its work when the bus is enumerated and the device is discovered (as a bunch of PCI or USB IDs -- not as "this is a hard drive") and loads the module, therefore making udev trigger. How does the 2.6.15 udev take on hotplug's role?
================================================================= To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
