> Remember that udev and sysfs are written by the same people, working together off-list. They're free to break the exported data format on a whim, because they

> Remember that udev and sysfs are written by the same people, working together off-list. They're free to break the exported data format on a whim, because they write the code at both ends and fundamentally they're talking to themselves. They honestly say you can't expect a new kernel to work with an old udev, and they say it with a straight face. (To me, this sounds like saying you can't expect a new kernel to work with an old version of ps, because of /proc.) > Documentation is a threat to this way of working, because it would impose restrictions on them. A spec is only of use if you introduce the radical idea that the information exported by sysfs exists for some purpose _other_ than simply to provide udev with information (and a specific version of udev matched to that kernel version, at that). http://lkml.iu.edu/hypermail/linux/kernel/0707.2/4230.html http://lkml.iu.edu/hypermail/linux/kernel/0707.2/4230.html (http://www.landley.net/notes-2015.html#05-07-2015 http://www.landley.net/notes-2015.html#05-07-2015)