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    SubjectRe: DEVFSv50 and /dev/fb? (or /dev/fb/? ???)
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    > > Dev_fs breaks completely under such circumstances you mean. Firewire and USB
    > > need potentially quite a lot of nonvolatile state storing. For that they need
    > > a daemon if they have a daemon they don't need devfs
    >
    > What state are you referring to? The permissions? And how many device
    > nodes are you talking about?

    Well for USB you have to remember the state of every device plugged into
    the system on a permanent basis. Not only is this needed for things like hot
    plugging when a device loses its settings as you move it between ports but
    also to ensure that when you plug it back in it keeps its old configuration
    from last use on this machine.

    The amount of state per device isnt really bounded, although I would expect
    it to be small. The point I was making is you do this by having a usb daemon
    sitting around getting "someone plugged this USB device in, its serial id
    is blah, its address is xyz and its a camera" and taking action in user
    space accordingly

    Policy in user space

    The pcmcia services also use this technique.


    So it doesnt matter if you are using devfs or not - the daemon will be making
    the device files in either and firing things up as needed. It has more to fire
    up than just devices though - insert a mouse - perhaps that loads gpm ?

    Alan


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