3 The default install location moved from /lib/udev to /usr/lib/udev
4 to support systems without the / vs. /usr split. --libbexecdir=
5 can still be configured to install things to the rootfs.
7 The udevadm tool moved from /sbin to /usr/bin. Some tools expect
8 udevadm in 'sbin'. A symlink to udevadm in 'bin' needs to be
9 manually created if needed. Alternatively --bindir=/sbin installs
12 The systemd socket files use PassCred=yes, which requires systemd
15 The blkid tool is no longer called from udev rules. Udev links directly
18 The udev build system only creates a .xz tarball now.
28 The udev daemon moved to /lib/udev/udevd. Non-systemd init systems
29 and non-dracut initramfs image generators need to change the init
30 scripts. Alternatively the udev build needs to move udevd back to
31 /sbin or create a symlink in /sbin, which is not done by default.
33 The path_id, usb_id, input_id tools are built-in commands now and
34 the stand-alone tools do not exist anymore. Static lists of file in
35 initramfs generators need to be updated. For testing, the commands
36 can still be executed standalone with 'udevadm test-builtin <cmd>'.
38 The fusectl filesystem is no longer mounted directly from udev.
39 Systemd systems will take care of mounting fusectl and configfs
40 now. Non-systemd systems need to ship their own rule if they
41 need these filesystems auto-mounted.
43 The long deprecated keys: SYSFS=, ID=, BUS= have been removed.
45 The support for 'udevadm trigger --type=failed, and the
46 RUN{fail_event_on_error} attribute was removed.
48 The udev control socket is now created in /run/udev/control
49 and no longer as an abstract namespace one.
51 The rules to create persistent network interface and cdrom link
52 rules automatically in /etc/udev/rules.d/ have been disabled by
53 default. Explicit configuration will be required for these use
54 cases, udev will no longer try to write any persistent system
55 configuration from a device hotplug path.
61 The udev-acl extra is no longer enabled by default now. To enable it,
62 --enable-udev_acl needs to be given at ./configure time. On systemd
63 systems, the udev-acl rules prevent it from running as the functionality
70 Udev now enables kernel media-presence polling if available. Part
71 of udisks optical drive tray-handling moved to cdrom_id: The tray
72 is locked as soon as a media is detected to enable the receiving
73 of media-eject-request events. Media-eject-request events will
76 Libudev enumerate is now able to enumerate a subtree of a given
79 The mobile-action-modeswitch modeswitch tool was deleted. The
80 functionality is provided by usb_modeswitch now.
86 The systemd service files require systemd version 28. The systemd
87 socket activation make it possible now to start 'udevd' and 'udevadm
92 Fix bug in control message handling, which can lead to a failing
93 udevadm control --exit. Thanks to Jürg Billeter for help tracking
100 We require at least Linux kernel 2.6.32 now. Some platforms might
101 require a later kernel that supports accept4() and similar, or
102 need to backport the trivial syscall wiring to the older kernels.
104 The hid2hci tool moved to the bluez package and was removed.
106 Many of the extras can be --enable/--disabled at ./configure
107 time. The --disable-extras option was removed. Some extras have
108 been disabled by default. The current options and their defaults
109 can be checked with './configure --help'.
115 Udev logs a warning now if /run is not writable at udevd
116 startup. It will still fall back to /dev/.udev, but this is
117 now considered a bug.
119 The running udev daemon can now cleanly shut down with:
120 udevadm control --exit
122 Udev in initramfs should clean the state of the udev database
123 with: udevadm info --cleanup-db which will remove all state left
124 behind from events/rules in initramfs. If initramfs uses
125 --cleanup-db and device-mapper/LVM, the rules in initramfs need
126 to add OPTIONS+="db_persist" for all dm devices. This will
127 prevent removal of the udev database for these devices.
129 Spawned programs by PROGRAM/IMPORT/RUN now have a hard timeout of
130 120 seconds per process. If that timeout is reached the spawned
131 process will be killed. The event timeout can be overwritten with
134 If systemd is used, udev gets now activated by netlink data.
135 Systemd will bind the netlink socket which will buffer all data.
136 If needed, such setup allows a seemless update of the udev daemon,
137 where no event can be lost during a udevd update/restart.
138 Packages need to make sure to: systemctl stop udev.socket udev.service
139 or 'mask' udev.service during the upgrade to prevent any unwanted
140 auto-spawning of udevd.
141 This version of udev conflicts with systemd version below 25. The
142 unchanged service files will not wirk correctly.
148 The udev runtime data moved from /dev/.udev/ to /run/udev/. The
149 /run mountpoint is supposed to be a tmpfs mounted during early boot,
150 available and writable to for all tools at any time during bootup,
151 it replaces /var/run/, which should become a symlink some day.
153 If /run does not exist, or is not writable, udev will fall back using
156 On systemd systems with initramfs and LVM used, packagers must
157 make sure, that the systemd and initramfs versions match. The initramfs
158 needs to create the /run mountpoint for udev to store the data, and
159 mount this tmpfs to /run in the rootfs, so the that the udev database
160 is preserved for the udev version started in the rootfs.
162 The command 'udevadm info --convert-db' is gone. The udev daemon
163 itself, at startup, converts any old database version if necessary.
165 The systemd services files have been reorganized. The udev control
166 socket is bound by systemd and passed to the started udev daemon.
167 The udev-settle.service is no longer active by default. Services which
168 can not handle hotplug setups properly need to actively pull it in, to
169 act like a barrier. Alternatively the settle service can be unconditionally
170 'systemctl'enabled, and act like a barrier for basic.target.
172 The fstab_import callout is no longer built or installed. Udev
173 should not be used to mount, does not watch changes to fstab, and
174 should not mirror fstab values in the udev database.
180 New and updated keymaps.
186 The udev database has changed, After installation of a new udev
187 version, 'udevadm info --convert-db' should be called, to let the new
188 udev/libudev version read the already stored data.
190 udevadm now supports quoting of property values, and prefixing of
192 $ udevadm info --export --export-prefix=MY_ --query=property -n sda
195 MY_DEVNAME='/dev/sda'
199 libudev now supports:
200 udev_device_get_is_initialized()
201 udev_enumerate_add_match_is_initialized()
202 to be able to skip devices the kernel has created , but udev has
205 libudev now supports:
206 udev_device_get_usec_since_initialized()
207 to retrieve the "age" of a udev device record.
209 GUdev supports a more generic GUdevEnumerator class, udev TAG
210 handling, device initialization and timestamp now.
212 The counterpart of /sys/dev/{char,block}/$major:$minor,
213 /dev/{char,block}/$major:$minor symlinks are now unconditionally
214 created, even when no rule files exist.
216 New and updated keymaps.
222 GUdev moved from /usr to /.
232 Persistent network naming rules are disabled inside of Qemu/KVM now.
234 New and updated keymaps.
236 Udev gets unconditionally enabled on systemd installations now. There
237 is no longer the need to to run 'systemctl enable udev.service'.
251 New and fixed keymaps.
253 Install systemd service files if applicable.
259 All distribution specific rules are removed from the udev source tree,
260 most of them are no longer needed. The Gentoo rules which allow to support
261 older kernel versions, which are not covered by the default rules anymore
262 has moved to rules/misc/30-kernel-compat.rules.
268 The option --debug-trace and the environemnt variable UDEVD_MAX_CHILDS=
269 was removed from udevd.
271 Udevd now checks the kernel commandline for the following variables:
272 udev.log-priority=<syslog priority>
273 udev.children-max=<maximum number of workers>
274 udev.exec-delay=<seconds to delay the execution of RUN=>
275 to help debuging coldplug setups where the loading of a kernel
276 module crashes the system.
278 The subdirectory in the source tree rules/packages has been renamed to
279 rules/arch, anc contains only architecture specific rules now.
289 Now the udev daemon itself, does on startup:
290 - copy the content of /lib/udev/devices to /dev
291 - create the standard symlinks like /dev/std{in,out,err},
292 /dev/core, /dev/fd, ...
293 - use static node information provided by kernel modules
294 and creates these nodes to allow module on-demand loading
295 - possibly apply permissions to all ststic nodes from udev
296 rules which are annotated to match a static node
298 The default mode for a device node is 0600 now to match the kernel
299 created devtmpfs defaults. If GROUP= is specified and no MODE= is
300 given the default will be 0660.
306 Udev now gradually starts to pass control over the primary device nodes
307 and their names to the kernel, and will in the end only manage the
308 permissions of the node, and possibly create additional symlinks.
309 As a first step NAME="" will be ignored, and NAME= setings with names
310 other than the kernel provided name will result in a logged warning.
311 Kernels that don't provide device names, or devtmpfs is not used, will
312 still work as they did before, but it is strongly recommended to use
313 only the same names for the primary device node as the recent kernel
314 provides for all devices.
318 Fix broken firmware loader search path.
324 "udevadm trigger" defaults to "change" events now instead of "add"
325 events. The "udev boot script" might need to add "--action=add" to
326 the trigger command if not already there, in case the initial coldplug
327 events are expected as "add" events.
329 The option "all_partitons" was removed from udev. This should not be
330 needed for usual hardware. Udev can not safely make assumptions
331 about non-existing partition major/minor numbers, and therefore no
332 longer provide this unreliable and unsafe option.
334 The option "ignore_remove" was removed from udev. With devtmpfs
335 udev passed control over device nodes to the kernel. This option
336 should not be needed, or can not work as advertised. Neither
337 udev nor the kernel will remove device nodes which are copied from
338 the /lib/udev/devices/ directory.
340 All "add|change" matches are replaced by "!remove" in the rules and
341 in the udev logic. All types of events will update possible symlinks
342 and permissions, only "remove" is handled special now.
344 The modem modeswitch extra was removed and the external usb_modeswitch
345 program should be used instead.
347 New and fixed keymaps.
357 Kernels with SYSFS_DEPRECATED=y are not supported since a while. Many users
358 depend on the current sysfs layout and the information not available in the
359 deprecated layout. All remaining support for the deprecated sysfs layout is
364 Fix for a possible endless loop in the new input_id program.
370 The option "ignore_device" does no longer exist. There is no way to
371 ignore an event, as libudev events can not be suppressed by rules.
372 It only prevented RUN keys from being executed, which results in an
373 inconsistent behavior in current setups.
375 BUS=, SYSFS{}=, ID= are long deprecated and should be SUBSYSTEM(S)=,
376 ATTR(S){}=, KERNEL(S)=. It will cause a warning once for every rule
379 The support for the deprecated IDE devices has been removed from the
380 default set of rules. Distros who still care about non-libata drivers
381 need to add the rules to the compat rules file.
383 The ID_CLASS property on input devices has been replaced by the more accurate
384 set of flags ID_INPUT_{KEYBOARD,KEY,MOUSE,TOUCHPAD,TABLET,JOYSTICK}. These are
385 determined by the new "input_id" prober now. Some devices, such as touchpads,
386 can have several classes. So if you previously had custom udev rules which e. g.
387 checked for ENV{ID_CLASS}=="kbd", you need to replace this with
388 ENV{ID_INPUT_KEYBOARD}=="?*".
394 To support DEVPATH strings larger than the maximum file name length, the
395 private udev database format has changed. If some software still reads the
396 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
397 Please do not port anything to the new format again, everything in /dev/.udev
398 is and always was private to udev, and may and will change any time without
401 Multiple devices claiming the same names in /dev are limited to symlinks
402 only now. Mixing identical symlink names and node names is not supported.
403 This reduces the amount of data in the database significantly.
405 NAME="%k" causes a warning now. It's is and always was completely superfluous.
406 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
409 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
410 if they are not the default. To support older kernels, the NAME= rules need to
411 be added to the compat rules file.
413 Symlinks to udevadm with the old command names are no longer resolved to
414 the udevadm commands.
416 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.1 is
419 The option "last_rule" does no longer exist. Its use breaks too many
420 things which expect to be run from independent later rules, and is an idication
421 that something needs to be fixed properly instead.
423 The gudev API is no longer marked as experimental,
424 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
425 is enabled by default now. Various projects already depend on introspection
426 information to bind dynamic languages to the gudev interfaces.
432 The udevadm trigger "--retry-failed" option, which is replaced since quite
433 a while by "--type=failed" is removed.
435 The failed tracking was not working at all for a few releases. The RUN
436 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
437 default is not to track any failing RUN executions.
439 New keymaps, new modem, hid2hci updated.
443 Fix possible crash in udevd when worker processes are busy, rules are
444 changed at the same time, and workers get killed to reload the rules.
450 Properties set with ENV{.FOO}="bar" are marked private by starting the
451 name with a '.'. They will not be stored in the database, and not be
452 exported with the event.
454 Firmware files are looked up in:
455 /lib/firmware/updates/$(uname -r)
456 /lib/firmware/updates
457 /lib/firmware/$(uname -r)
461 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
462 ata_id, instead of scsi_id, is the default tool now for ATA devices.
468 The configure options have changed because another library needs to be
469 installed in a different location. Instead of exec_prefix and udev_prefix,
470 libdir, rootlibdir and libexecdir are used. The Details are explained in
473 Event processes now get re-used after they handled an event. This reduces
474 the number of forks and the pressure on the CPU significantly, because
475 cloned event processes no longer cause page faults in the main daemon.
476 After the events have settled, a few worker processes stay around for
477 future events, all others get cleaned up.
479 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
480 Also inotify support is mandatory now to run udev.
482 The format of the queue exported by the udev damon has changed. There is
483 no longer a /dev/.udev/queue/ directory. The current event queue can be
484 accessed with udevadm settle and libudedv.
486 Libudev does not have the unstable API header anymore. From now on,
487 incompatible changes will be handled by bumping the library major version.
489 To build udev from the git tree gtk-doc is needed now. The tarballs will
490 build without it and contain the pre-built documentation. An online copy
492 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
494 The tools from the udev-extras repository have been merged into the main
495 udev repository. Some of the extras have larger external dependencies, and
496 they can be disabled with the configure switch --disable-extras.
502 The program vol_id and the library libvolume_id are removed from the
503 repository. Libvolume_id is merged with libblkid from the util-linux-ng
504 package. Persistent disk links for label and uuid depend on the
505 util-linux-ng version (2.15) of blkid now. Older versions of blkid
506 can not be used with udev.
508 Libudev allows to subscribe to udev events. To prevent unwanted messages
509 to be delivered, and waking up the subscribing process, a filter can be
510 installed, to drop messages inside a kernel socket filter. The filters
511 match on the <subsytem>:<devtype> properties of the device.
512 This is part of the ongoing effort to replace HAL, and switch current
513 users over to directly use libudev.
514 Libudev is still marked as experimental, and its interface might
515 eventually change if needed, but no major changes of the currently exported
516 interface are expected anymore, and a first stable release should happen
519 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
520 is not supported since while and udevd will log an error message at
521 startup. It should still be able to boot-up, but advanced rules and system
522 services which depend on the information not available in the old sysfs
523 format will fail to work correctly.
525 DVB device naming is supplied by the kernel now. In case older kernels
526 need to be supported, the old shell script should be added to a compat
533 The processed udev events get send back to the netlink socket. Libudev
534 provides access to these events. This is work-in-progress, to replace
535 the DeviceKit daemon functionality directly with libudev. There are
536 upcoming kernel changes to allow non-root users to subcribe to these
543 "udevadm settle" now optionally accepts a range of events to wait for,
544 instead of waiting for "all" events.
550 The installed watch for block device metadata changes is now removed
551 during event hadling, because some (broken) tools may be called from udev
552 rules and (wrongly) open the device with write access. After the finished
553 event handling the watch is restored.
559 Device nodes can be watched for changes with inotify with OPTIONS="watch".
560 If closed after being opened for writing, a "change" uevent will occur.
561 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
567 The udevadm test command has no longer a --force option, nodes and symlinks
568 are always updated with a test run now.
570 The udevd daemon can be started with --resolve-names=never to avoid all user
571 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
572 lookup user and groups every time events are handled.
578 We are currently merging the Ubuntu rules in the udev default rules,
579 and get one step closer to provide a common Linux /dev setup, regarding
580 device names, symlinks, and default device permissions. On udev startup,
581 we now expect the following groups to be resolvable to their ids with
583 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
584 LDAP setups need to make sure, that these groups are always resolvable at
585 bootup, with only the rootfs mounted, and without network access available.
587 Some systems may need to add some new, currently not used groups, or need
588 to add some users to new groups, but the cost of this change is minimal,
589 compared to the pain the current, rather random, differences between the
590 various distributions cause for upstream projects and third-party vendors.
592 In general, "normal" users who log into a machine should never be a member
593 of any such group, but the device-access should be managed by dynamic ACLs,
594 which get added and removed for the specific users on login/logout and
595 session activity/inactivity. These groups are only provided for custom setups,
596 and mainly system services, to allow proper privilege separation.
597 A video-streaming daemon uid would be a member of "audio" and "video", to get
598 access to the sound and video devices, but no "normal" user should ever belong
599 to the "audio" group, because he could listen to the built-in microphone with
600 any ssh-session established from the other side of the world.
602 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
603 which do not depend on the kernel device name. As usual, unique
604 devices - only a single one per product connected, or a real
605 USB serial number in the device - are always found with the same
606 name in the by-id/ directory.
607 Completely identical devices may overwrite their names in by-id/
608 and can only be found reliably in the by-path/ directory. Devices
609 specified by by-path/ must not change their connection, like the
610 USB port number they are plugged in, to keep their name.
612 To support some advanced features, Linux 2.6.22 is the oldest supported
613 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
614 supported. Older kernels should still work, and devices nodes should be
615 reliably created, but some rules and libudev will not work correctly because
616 the old kernels do not provide the expected information or interfaces.
622 Fix for a possible segfault while swapping network interface names in udev
629 The group "video" is part of the default rules now.
633 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
634 block devices in some cases. No common distro uses this option anymore,
635 and we do not get enough testing for this and recent udev versions. If
636 this option is not needed to run some old distro with a new kernel,
637 it should be disabled in the kernel config.
639 Bugfix for the $links substitution variable, which may crash if no links
640 are created. This should not happen in usual setups because we always
641 create /dev/{block,char}/ links.
643 The strings of the parsed rules, which are kept in memory, no longer
644 contain duplicate entries, or duplicate tails of strings. This, and the
645 new rules parsing/matching code reduces the total in-memory size of
646 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
649 The export of DEVTYPE=disk/partition got removed from the default
650 rules. This value is available from the kernel. The pnp shell script
651 modprobe hack is removed from the default rules. ACPI devices have _proper_
652 modalias support and take care of the same functionality.
653 Installations which support old kernels, but install current default
654 udev rules may want to add that to the compat rules file.
656 Libvolume_id now always probes for all known filesystems, and does not
657 stop at the first match. Some filesystems are marked as "exclusive probe",
658 and if any other filesytem type matches at the same time, libvolume_id
659 will, by default, not return any probing result. This is intended to prevent
660 mis-detection with conflicting left-over signatures found from earlier
661 file system formats. That way, we no longer depend on the probe-order
662 in case of multiple competing signatures. In some setups the kernel allows
663 to mount a volume with just the old filesystem signature still in place.
664 This may damage the new filesystem and cause data-loss, just by mounting
665 it. Because volume_id can not decide which one the correct signature is,
666 the wrong signatures need to be removed manually from the volume, or the
667 volume needs to be reformatted, to enable filesystem detection and possible
672 Fix segfault if compiled without optimization and dbg() does not get
673 compiled out and uses variables which are not available.
677 Bugfixes. (And maybe new bugs. :))
679 The rule matching engine got converted from a rule list to a token
680 array which reduced the in-memory rules representation of a full
681 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
682 Limits like 5 ENV and ATTR matches, and one single instance for most
683 other keys per rule are gone.
685 The NAME assignment is no longer special cased. If later rules assign
686 a NAME value again, the former value will be overwritten. As usual
687 for most other keys, the NAME value can be protected by doing a final
688 assignment with NAME:="<value>".
690 All udev code now uses libudev, which is also exported. The library
691 is still under development, marked as experimental, and its interface
692 may change as long as the DeviceKit integration is not finished.
694 Many thanks to Alan Jenkins for his continuous help, and finding and
695 optimizing some of the computing expensive parts.
701 Kernel devices and device nodes are connected now by reverse indizes in
702 /sys and /dev. A device number retrieved by a stat() or similar, the
703 kernel device directory can be found by looking up:
704 /sys/dev/{block,char}/<maj>:<min>
705 and the device node of the same device by looking up:
706 /dev/{block,char}/<maj>:<min>
710 Fix recently introduced bug, which caused a compilation without large
711 file support, where vol_id does not recognize raid signatures at the end
714 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
715 Seems some kernel versions prevent the creation of the ieee-* links,
716 so people used the scsi-* link which disappeared now.
718 More libudev work. Almost all udevadm functionality comes from libudev
721 udevadm trigger has a new option --type, which allows to trigger events
722 for "devices", for "subsystems", or "failed" devices. The old option
723 --retry-failed" still works, but is no longer mentioned in the man page.
729 The udevadm info --device-id-of-file= output has changed to use
730 the obvious format. Possible current users should use the --export
731 option which is not affected.
733 The old udev commands symlinks to udevadm are not installed, if
734 these symlinks are used, a warning is printed.
740 Optical drive's media is no longer probed for raid signatures,
741 reading the end of the device causes some devices to malfunction.
742 Also the offset of the last session found is used now to probe
745 The volume_id library got a major version number update to 1,
746 some deprecated functions are removed.
748 A shared library "libudev" gets installed now to provide access
749 to udev device information. DeviceKit, the successor of HAL, will
750 need this library to access the udev database and search sysfs for
752 The library is currently in an experimental state, also the API is
753 expected to change, as long as the DeviceKit integration is not
758 We use ./configure now. See INSTALL for details. Current
761 "/usr" - prefix for man pages, include files
763 "" - the root filesystem, prefix for libs and binaries
767 "lib" - directory name for libraries, not a path name
768 multilib 64bit systems may use "lib64" instead of "lib"
770 compile-in verbose debug messages
772 disable all logging and compile-out all log strings
774 link against SELInux libraries, to set the expected context
777 In the default rules, the group "disk" gets permissions 0660 instead
778 of 0640. One small step closer to unify distro rules. Some day, all
779 distros hopefully end up with the same set of rules.
781 No symlinks to udevadm are installed anymore, if they are still needed,
782 they should be provided by the package.
788 Default udev rules, which are not supposed to be edited by the user, should
789 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
790 the udev package and will be replaced with an update. Udev will pick up rule
792 /lib/udev/rules.d/ - default installed rules
793 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
794 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
795 It does not matter in which directory a rule file lives, all files are sorted
798 To help creating /dev/root, we have now:
799 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
802 In case the current --device-id-of-file is already used, please switch to
803 the --export format version, it saves the output parsing and the old
804 format will be changed to use ':' as a separator, like the format in the
809 Fix cdrom_id to properly recognize blank media.
815 Tape drive id-data is queried from /dev/bsg/* instead of the tape
816 nodes. This avoids rewinding tapes on open().
822 The symlinks udevcontrol and udevtrigger are no longer installed by
825 The scsi_id program does not depend on sysfs anymore. It can speak
826 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
827 data, which should solve some old problems with tape devices, where
828 we better do not open all tape device nodes to identify the device.
834 The cdrom_id program is replaced by an advanced version, which can
835 detect most common device types, and also properties of the inserted
836 media. This is part of moving some basic functionality from HAL into
837 udev (and the kernel).
843 The last WAIT_FOR_SYSFS rule is removed from the default rules.
845 The symlinks to udevadm for the debugging tools: udevmonitor and
846 udevtest are no longer created.
848 The symlinks to the udevadm man page for the old tool names are
851 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
852 should be prefixed with '@' to indicate that the path is not a
863 Udevstart is removed from the tree, it did not get installed for
864 a long time now, and is long replaced by trigger and settle.
870 All udev tools are merged into a single binary called udevadm.
871 The old names of the tools are built-in commands in udevadm now.
872 Symlinks to udevadm, with the names of the old tools, provide
873 the same functionality as the standalone tools. There is also
874 only a single udevadm.8 man page left for all tools.
876 Tools like mkinitramfs should be checked, if they need to include
877 udevadm in the list of files.
887 The etc/udev/rules.d/ directory now contains a default set of basic
888 udev rules. This initial version is the result of a rules file merge
889 of Fedora and openSUSE. For these both distros only a few specific
890 rules are left in their own file, named after the distro. Rules which
891 are optionally installed, because they are only valid for a specific
892 architecture, or rules for subsystems which are not always used are
893 in etc/udev/packages/.
899 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
900 actions by dynamically created rules.
902 SYMLINK=="<value>" matches agains the entries in the list of
903 currently defined symlinks. The links are not created in the
904 filesystem at that point in time, but the values can be matched.
906 RUN{ignore_error}+="<program>" will ignore any exit code from the
907 program and not record as a failed event.
913 Final merge of patches/features from the Ubuntu package.
919 Control characters in filesystem label strings are no longer silenty
920 removed, but hex-encoded, to be able to uniquely identify the device
921 by its symlink in /dev/disk/by-label/.
922 If libvolume_id is used by mount(8), LABEL= will work as expected,
923 if slashes or other characters are used in the label string.
925 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
926 can be specified now. The TEST key accepts an optional mode mask
927 TEST{0100}=="<is executable file>".
929 Scsi_id now supports a mode without expecting scsi-specific sysfs
930 entries to allow the extraction of cciss-device persistent properties.
936 In the future, we may see uuid's which are just simple character
937 strings (see the DDF Raid Specification). For that reason vol_id now
938 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
939 the creation of symlinks, the *_SAFE values ensure, that no control
940 or whitespace characters are used in the filename.
942 Possible users of libvolume_id, please use the volume_id_get_* functions.
943 The public struct will go away in a future release of the library.
949 Removal of useless extras/eventrecorder.sh.
959 The directory multiplexer for dev.d/ and hotplug.d are finally removed
960 from the udev package.
966 Symlinks can have priorities now, the priority is assigned to the device
967 and specified with OPTIONS="link_priority=100". Devices with higher
968 priorities overwrite the symlinks of devices with lower priorities.
969 If the device that currently owns the link, goes away, the symlink
970 will be removed, and recreated, pointing to the next device with the
971 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
972 more reliable, if multiple devices contain the same metadata and overwrite
975 The dasd_id program is removed from the udev tree, and dasdinfo, with the
976 needed rules, are part of the s390-tools now.
978 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
979 we may get the scsi sysfs mess fixed some day, and this will only catch
980 the devices we are looking for.
982 USB serial numbers for storage devices have the target:lun now appended,
983 to make it possibble to distinguish broken multi-lun devices with all
984 the same SCSI identifiers.
986 Note: The extra "run_directory" which searches and executes stuff in
987 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
988 with the next release. Make sure, that you don't use it anymore, or
989 provides your own implementation of that inefficient stuff.
990 We are tired of reports about a "slow udev", because these directories
991 contain stuff, that runs with _every_ event, instead of using rules,
992 that run programs only for the matching events.
1002 DRIVER== will match only for devices that actually have a real
1003 driver. DRIVERS== must be used, if parent devices should be
1004 included in the match.
1006 Libvolume_id's "linux_raid" detection needed another fix.
1014 Add additional check to volume_id detection of via_raid, cause
1015 some company decided to put a matching pattern all over the empty
1016 storage area of their music players.
1020 Fix path_id for SAS devices.
1024 The udev daemon can be started with --debug-trace now, which will
1025 execute all events serialized to get a chance to catch a possible
1026 action that crashes the box.
1028 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
1029 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
1030 are excluded from the warning. Referencing parent attributes directly
1031 may break when something in the kernel driver model changes. Udev will
1032 just find the attribute by walking up the parent chain.
1034 Udevtrigger now sorts the list of devices depending on the device
1035 dependency, so a "usb" device is triggered after the parent "pci"
1040 Revert persistent-storage ata-serial '_' '-' replacement.
1046 Udevtrigger can now filter the list of devices to be triggered. Matches
1047 for subsystems or sysfs attributes can be specified.
1049 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
1050 zero-sized files to avoid pointing to /sys and confuse broken tools which
1051 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
1054 The rules and scripts to create udev rules for persistent network
1055 devices and optical drives are in the extras/rules_generator directory
1056 now. If you use something similar, please consider replacing your own
1057 version with this, to share the support effort. The rule_generator
1058 installs its own rules into /etc/udev/rules.d.
1060 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
1061 the rule_generator depends on cdrom_id to be called in an earlier rule.
1067 Renaming of some key names (the old names still work):
1068 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
1069 (The behavior of the key DRIVER will change soon in one of the next
1070 releases, to match only the event device, please switch to DRIVERS
1071 instead. If DRIVER is used, it will behave like DRIVERS, but an error
1073 With the new key names, we have a more consistent and simpler scheme.
1074 We can match the properties of the event device only, with: KERNEL,
1075 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
1076 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
1077 longer mentioned in the man page and should be switched in the rule
1080 ATTR{file}="value" can be used now, to write to a sysfs file of the
1081 event device. Instead of:
1082 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
1084 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
1086 All the PHYSDEV* keys are deprecated and will be removed from a
1088 PHYDEVPATH - is the path of a parent device and should not be
1090 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
1091 matched with SUBSYSTEMS==
1092 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
1093 Newer kernels will have DRIVER in the environment,
1094 for older kernels udev puts in. Class device will
1095 no longer carry this property of a parent and
1096 DRIVERS== can be used to match such a parent value.
1097 Note that ENV{DRIVER} is only available for a few bus devices, where
1098 the driver is already bound at device event time. On coldplug, the
1099 events for a lot devices are already bound to a driver, and they will have
1100 that value set. But on hotplug, at the time the kernel creates the device,
1101 it can't know what driver may claim the device after that, therefore
1102 in most cases it will be empty.
1104 Failed events should now be re-triggered with:
1105 udevtrigger --retry-failed.
1106 Please switch to this command, so we keep the details of the /dev/.udev/failed/
1107 files private to the udev tools. We may need to switch the current symlink
1108 target, cause some obviously broken tools try to scan all files in /dev
1109 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
1110 million times. This takes ages on slow boxes.
1112 The udevinfo attribute walk (-a) now works with giving a device node
1113 name (-n) instead of a devpath (-p). The query now always works, also when
1114 no database file was created by udev.
1116 The built-in /etc/passwd /etc/group parser is removed, we always depend on
1117 getpwnam() and getgrnam() now. One of the next releases will depend on
1118 fnmatch() and may use getopt_long().
1122 Bugfixes and small improvements.
1126 Fix path_id for recent kernels.
1132 Added support for swapping network interface names, by temporarily
1133 renaming the device and wait for the target name to become free.
1137 The built-in MODALIAS key and substitution is removed.
1141 The binary firmware helper is replaced by the usual simple
1142 shell script. Udevsend is removed from the tree.
1150 Some more keys require the correct use of '==' and '=' depending
1151 on the kind of operation beeing an assignment or a match. Rules
1152 with invalid operations are skipped and logged to syslog. Please
1153 test with udevtest if the parsing of your rules throws errors and
1154 fix possibly broken rules.
1158 Provide "udevsettle" to wait for all current udev events to finish.
1159 It also watches the current kernel netlink queue by comparing the
1160 even sequence number to make sure that there are no current pending
1161 events that have not already arrived in the daemon.
1165 Fix rule to skip persistent rules for removable IDE devices, which
1166 also skipped optical IDE drives.
1168 All *_id program are installed in /lib/udev/ by default now.
1170 No binary is stripped anymore as this should be done in the
1171 packaging process and not at build time.
1173 libvolume_id is provided as a shared library now and vol_id is
1174 linked against it. Also one of the next HAL versions will require
1175 this library, and the HAL build process will also require the
1176 header file to be installed. The copy of the same code in HAL will
1177 be removed to have only a single copy left on the system.
1181 Add persistent links for SCSI tapes. The rules file is renamed
1182 to 60-persistent-storage.rules.
1184 Create persistent path for usb devices. Can be used for all sorts
1185 of devices that can't be distinguished by other properties like
1186 multiple identical keyboards and mice connected to the same box.
1188 Provide "udevtrigger" program to request events on coldplug. The
1189 shell script is much too slow with thousends of devices.
1193 Fix persistent disk rules to exclude removable IDE drives.
1195 Warn if %e, $modalias or MODALIAS is used.
1199 Fix queue export, which wasn't correct for subsequent add/remove
1200 events for the same device.
1204 Fix cramfs detection on big endian.
1206 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
1211 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
1212 attributes were only checked at the parent device that matched the
1213 by BUS requested subsystem. Fix it to also look at the device we
1214 received the event for.
1216 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
1221 Fix a bug where NAME="" would prevent RUN from beeing executed.
1223 RUN="/bin/program" does not longer automatically add the subsystem
1224 as the first parameter. This is from the days of /sbin/hotplug
1225 which is dead now and it's just confusing to need to add a space at
1226 the end of the program name to prevent this.
1227 If you use rules that need the subsystem as the first parameter,
1228 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
1229 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
1233 The udev man page has moved to udev(7) as it does not describe a command
1234 anymore. The programs udev, udevstart and udevsend are no longer installed
1235 by default and must be copied manually, if they should be installed or
1236 included in a package.
1238 Fix a bug where "ignore_device" could run earlier collected RUN keys before
1239 the ignore rule was applied.
1241 More preparation for future sysfs changes. usb_id and scsi_id no longer
1242 depend on a magic order of devices in the /devices chain. Specific devices
1243 should be requested by their subsytem.
1245 This will always find the scsi parent device without depending on a specific
1247 dev = sysfs_device_get(devpath);
1248 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
1250 The "device" link in the current sysfs layout will be automatically
1251 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
1252 parent in the devpath. If a device is requested by it's symlink, like all
1253 class devices in the new sysfs layout will look like, it gets automatically
1254 resolved and substituted with the real devpath and not the symlink path.
1257 A similar logic must be applied to _all_ sysfs users, including
1258 scripts, that search along parent devices in sysfs. The explicit use of
1259 the "device" link must be avoided. With the future sysfs layout all
1260 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
1261 back to the "class" or the "bus". The layout of the parent devices in
1262 /devices is not necessarily expected to be stable across kernel releases and
1263 searching for parents by their subsystem should make sysfs users tolerant
1264 for changed parent chains.
1268 Prepare udev to work with the experimental kernel patch, that moves
1269 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
1271 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
1272 moving the class devices to /sys/devices.
1274 Thanks again to Marco for help finding a hopefully nice compromise
1275 to make %b simpler and working again.
1279 Complete removal of libsysfs, replaced by simple helper functions
1280 which are much simpler and a bit faster. The udev daemon operatesentirely
1281 on event parameters and does not use sysfs for simple rules anymore.
1282 Please report any new bugs/problems, that may be caused by this big
1283 change. They will be fixed immediately.
1285 The enumeration format character '%e' is deprecated and will be
1286 removed sometimes from a future udev version. It never worked correctly
1287 outside of udevstart, so we can't use it with the new parallel
1288 coldplug. A simple enumeration is as useless as the devfs naming
1289 scheme, just get rid of both if you still use it.
1291 MODALIAS and $modalias is not needed and will be removed from one of
1292 the next udev versions, replace it in all rules with ENV{MODALIAS} or
1293 the sysfs "modalias" value.
1295 Thanks a lot to Marco for all his help on finding and fixing bugs.
1299 Let scsi_id request libata drive serial numbers from page 0x80.
1301 Renamed etc/udev/persistent.rules to persistent-disk.rules and
1302 added /dev/disk/by-name/* for device mapper device names.
1304 Removed %e from the man page. It never worked reliably outside
1305 of udevstart and udevstart is no longer recommended to use.
1309 Symlinks are now exported to the event environment. Hopefully it's no
1310 longer needed to run udevinfo from an event process, like it was
1311 mentioned on the hotplug list:
1312 UDEV [1134776873.702967] add@/block/sdb
1315 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
1319 Fix a problem if udevsend is used as the hotplug handler and tries to use
1320 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
1321 and this kind of problems will hopefully go away soon.
1325 All built-in logic to work around bad sysfs timing is removed with this
1326 version. The need to wait for sysfs files is almost fixed with a kernel
1327 version that doesn't work with this udev version anyway. Until we fix
1328 the timing of the "bus" link creation, the former integrated logic should
1329 be emulated by a rule placed before all other rules:
1330 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
1332 The option "udev_db" does no longer exist. All udev state will be in
1333 /$udev_root/.udev/ now, there is no longer an option to set this
1335 If the init script or something else used this value, just depend on
1336 this hardcoded path. But remember _all_content_ of this directory is
1337 still private to udev and can change at any time.
1339 Default location for rule sripts and helper programs is now: /lib/udev/.
1340 Everything that is not useful on the commandline should go into this
1341 directory. Some of the helpers in the extras folder are installed there
1342 now. The rules need to be changed, to find the helpers there.
1344 Also /lib/udev/devices is recommended as a directory where packages or
1345 the user can place real device nodes, which get copied over to /dev at
1346 every boot. This should replace the various solutions with custom config
1349 Udevsend does no longer start the udev daemon. This must be done with
1350 the init script that prepares /dev on tmpfs and creates the initial nodes,
1351 before starting the daemon.
1355 Silent a too verbose error logging for the old hotplug.d/ dev.d/
1358 The copy of klibc is removed. A systemwide installed version of klibc
1359 should be used to build a klibc udev now.
1363 NAME="" will not create any nodes, but execute RUN keys. To completely
1364 ignore an event the OPTION "ignore_device" should be used.
1366 After removal of the reorder queue, events with a TIMEOUT can be executed
1367 without any queuing now.
1371 Fixed bug in udevd, if inotify is not available. We depend on netlink
1372 uevents now, kernels without that event source will not work with that
1373 version of udev anymore.
1377 The rule parsing happens now in the daemon once at startup, all udev
1378 event processes inherit the already parsed rules from the daemon.
1379 It is shipped with SUSE10.0 and reduces heavily the system load at
1380 startup. The option to save precompiled rules and let the udev process
1381 pick the them up is removed, as it's no longer needed.
1383 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
1384 device. Libsysfs is changed to "translate" the requested link into the
1385 real device path, as it would happen with the hotplug event. Otherwise
1386 device removal and the udev database will not work.
1388 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1391 A few improvements for vol_id, the filesytem probing code.
1395 Fix a stupid typo in extras/run_directory for "make install".
1397 scsi_id creates the temporary devnode now in /dev for usage with a
1398 non-writable /tmp directory.
1400 The uevent kernel socket buffer can carry app. 50.000 events now,
1401 let's see who can break this again. :)
1403 The upcoming kernel will have a new input driver core integration.
1404 Some class devices are now symlinks to the real device. libsysfs
1405 needs a fix for this to work correctly. Udevstart of older udev
1406 versions will _not_ create these devices!
1410 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1415 A bunch of mostly trivial bugfixes. From now on no node name or
1416 symlink name can contain any character than plain whitelisted ascii
1417 characters or validated utf8 byte-streams. This is needed for the
1418 /dev/disk/by-label/* links, because we import untrusted data and
1419 export it to the filesystem.
1423 More bugfixes. If udevd was started from the kernel, we don't
1424 have stdin/stdout/stderr, which broke the forked tools in some
1429 Bugfix. udevstart event ordering was broken for a long time.
1430 The new run_program() uncovered it, because /dev/null was not
1431 available while we try to run external programs.
1432 Now udevstart should create it before we run anything.
1436 Minor bugfixes and some distro rules updates. If you don't have the
1437 persistent disk rules in /dev/disk/by-*/* on your distro, just
1438 grab it from here. :)
1442 We can use socket communication now to pass events from udev to
1444 RUN+="socket:/org/freedesktop/hal/udev_event"
1445 will pass the whole udev event to the HAL daemon without the need
1446 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1450 Mostly bugfixes and see ChangeLog.
1452 The test for the existence of an environment value should be
1454 ENV{KEY}=="*" to ENV{KEY}=="?*"
1455 because "*" will not fail anymore, if the key does not exist or
1460 Bugfixes and a few tweaks described in the ChangeLog.
1464 Mostly a Bugfix release.
1466 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1467 timing with custom rules.
1471 We changed the internal rule storage format. Our large rule files took
1472 2 MB of RAM, with the change we are down to 99kB.
1474 If the device-node has been created with default name and no symlink or
1475 options are to remenber, it is not longer stored in the udevdb. HAL will
1476 need to be updated to work correctly with that change.
1478 To overrride optimization flags, OPTFLAGS may be used now.
1486 Major changes happened with this release. The goal is to take over the
1487 complete kernel-event handling and provide a more efficient way to dispatch
1488 kernel events. Replacing most of the current shell script logic and the
1489 kernel forked helper with a netlink-daemon and a rule-based event handling.
1491 o udevd listens to netlink events now. The first valid netlink event
1492 will make udevd ignore any message from udevsend that contains a
1493 SEQNUM, to avoid duplicate events. The forked events can be disabled
1495 echo "" > /proc/sys/kernel/hotplug
1496 For full support, the broken input-subsytem needs to be fixed, not to
1497 bypass the driver core.
1499 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1500 removed from udev itself and must be emulated by calling small
1501 helper binaries provided in the extras folder:
1502 make EXTRAS=extras/run_directory/
1503 will build udev_run_devd and udev_run_hotplugd, which can be called
1504 from a rule if needed:
1505 RUN+="/sbin/udev_run_hotplugd"
1506 The recommended way to handle this is to convert all the calls from
1507 the directories to explicit udev rules and get completely rid of the
1508 multiplexing. (To catch a ttyUSB event, you now no longer need to
1509 fork and exit 300 tty script instances you are not interested in, it
1510 is just one rule that matches exactly the device.)
1512 o udev handles now _all_ events not just events for class and block
1513 devices, this way it is possible to control the complete event
1514 behavior with udev rules. Especially useful for rules like:
1515 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1517 o As used in the modalias rule, udev supports now textual
1518 substitution placeholder along with the usual format chars. This
1519 needs to be documented, for now it's only visible in udev_rules_parse.c.
1521 o The rule keys support now more operations. This is documented in the
1522 man page. It is possible to add values to list-keys like the SYMLINK
1523 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1524 Also "final"-assignments are supported by using KEY:="value", which will
1525 prevent changing the key by any later rule.
1527 o kernel 2.6.12 has the "detached_state" attribute removed from
1528 sysfs, which was used to recognize sysfs population. We switched that
1529 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1530 Running this udev version on older kernels may cause a short delay for
1533 o To provide infrastructure for persistent device naming, the id programs:
1534 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1535 to export the probed data in environment key format:
1536 pim:~ # /sbin/ata_id --export /dev/hda
1537 ID_MODEL=HTS726060M9AT00
1538 ID_SERIAL=MRH401M4G6UM9B
1539 ID_REVISION=MH4OA6BA
1541 The following rules:
1542 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1543 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1546 kay@pim:~> tree /dev/disk
1549 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1550 | `-- IBM-Memory_Key -> ../../sda
1552 | |-- swap -> ../../hda1
1553 | |-- date -> ../../sda1
1554 | `-- home -> ../../hda3
1556 |-- 2E08712B0870F2E7 -> ../../hda3
1557 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1558 |-- E845-7A89 -> ../../sda1
1559 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1561 The IMPORT= operation will import these keys in the environment and make
1562 it available for later PROGRAM= and RUN= executed programs. The keys are
1563 also stored in the udevdb and can be queried from there with one of the
1566 o A few binaries are silently added to the repository, which can be used
1567 to replay kernel events from initramfs instead of using coldplug. udevd
1568 can be instructed now to queue-up events while the stored events from
1569 initramfs are filled into the udevd-queue. This code is still under
1570 development and there is no documentation now besides the code itself.
1571 The additional binaries get compiled, but are not installed by default.
1573 o There is also a temporary fix for a performance problem where too many
1574 events happen in parallel and every event needs to parse the rules.
1575 udev can now read precompiled rules stored on disk. This is likely to be
1576 replaced by a more elegant solution in a future udev version.
1580 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1581 Fix for libsysfs not to expect this file was added.
1585 All rules are applied now, but only the first matching rule with a NAME-key
1586 will be applied. All later rules with NAME-key are completely ignored. This
1587 way system supplied symlinks or permissions gets applied to user-defined
1591 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1592 to some rules, to keep the old behavior.
1594 The rules are read on "remove"-events too. That makes is possible to match
1595 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1596 instruct udev to ignore an event (OPTIONS="ignore_device").
1597 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1599 The new RUN-key supports rule-based execution of programs after device-node
1600 handling. This is meant as a general replacement for the dev.d/-directories
1601 to give fine grained control over the execution of programs.
1603 The %s{}-sysfs format char replacement values are searched at any of the
1604 devices in the device chain now, not only at the class-device.
1606 We support log priority levels now. The value udev_log in udev.conf is used
1607 to determine what is printed to syslog. This makes it possible to
1608 run a version with compiled-in debug messages in a production environment
1609 which is sometimes needed to find a bug.
1610 It is still possible to supress the inclusion of _any_ syslog usage with
1611 USE_LOG=false to create the smallest possible binaries if needed.
1612 The configured udev_log value can be overridden with the environment variable
1617 Possible use of a system-wide klibc:
1618 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1619 will link against an external klibc and our own version will be ignored.
1623 We support an unlimited count of symlinks now.
1625 If USE_STATIC=true is passed to a glibc build, we link statically and use
1626 a built-in userdb parser to resolve user and group names.
1628 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1629 we walk up the chain of physical devices to find a match.
1631 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1632 easy to skip certain attribute matches without composing rules with weird
1633 character class negations like:
1634 KERNEL="[!s][!c][!d]*"
1635 this can now be replaced with:
1637 The current simple '=' is still supported, and should work as it does today,
1638 but existing rules should be converted if possible, to be better readable.
1640 We have new ENV{}== key now, to match against a maximum of 5 environment
1643 udevstart is its own binary again, because we don't need co carry this araound
1644 with every forked event.