5 The path_id, usb_id, input_id tools are built-in commands now
6 and the stand-alone tools do not exist anymore. For testing,
7 the commands can be run with 'udevadm test-builtin <cmd>'.
9 The fusectl filesystem is no longer mounted directly from udev.
10 Systemd systems will take care of mounting fusectl and configfs
11 now. Non-systemd systems need to ship their own rule if they
12 need these filesystems auto-mounted.
18 The udev-acl extra is no longer enabled by default now. To enable it,
19 --enable-udev_acl needs to be given at ./configure time. On systemd
20 systems, the udev-acl rules prevent it from running as the functionality
27 Udev now enables kernel media-presence polling if available. Part
28 of udisks optical drive tray-handling moved to cdrom_id: The tray
29 is locked as soon as a media is detected to enable the receiving
30 of media-eject-request events. Media-eject-request events will
33 Libudev enumerate is now able to enumerate a subtree of a given
36 The mobile-action-modeswitch modeswitch tool was deleted. The
37 functionality is provided by usb_modeswitch now.
43 The systemd service files require systemd version 28. The systemd
44 socket activation make it possible now to start 'udevd' and 'udevadm
49 Fix bug in control message handling, which can lead to a failing
50 udevadm control --exit. Thanks to Jürg Billeter for help tracking
57 We require at least Linux kernel 2.6.32 now. Some platforms might
58 require a later kernel that supports accept4() and similar, or
59 need to backport the trivial syscall wiring to the older kernels.
61 The hid2hci tool moved to the bluez package and was removed.
63 Many of the extras can be --enable/--disabled at ./configure
64 time. The --disable-extras option was removed. Some extras have
65 been disabled by default. The current options and their defaults
66 can be checked with './configure --help'.
72 Udev logs a warning now if /run is not writable at udevd
73 startup. It will still fall back to /dev/.udev, but this is
76 The running udev daemon can now cleanly shut down with:
77 udevadm control --exit
79 Udev in initramfs should clean the state of the udev database
80 with: udevadm info --cleanup-db which will remove all state left
81 behind from events/rules in initramfs. If initramfs uses
82 --cleanup-db and device-mapper/LVM, the rules in initramfs need
83 to add OPTIONS+="db_persist" for all dm devices. This will
84 prevent removal of the udev database for these devices.
86 Spawned programs by PROGRAM/IMPORT/RUN now have a hard timeout of
87 120 seconds per process. If that timeout is reached the spawned
88 process will be killed. The event timeout can be overwritten with
91 If systemd is used, udev gets now activated by netlink data.
92 Systemd will bind the netlink socket which will buffer all data.
93 If needed, such setup allows a seemless update of the udev daemon,
94 where no event can be lost during a udevd update/restart.
95 Packages need to make sure to: systemctl stop udev.socket udev.service
96 or 'mask' udev.service during the upgrade to prevent any unwanted
97 auto-spawning of udevd.
98 This version of udev conflicts with systemd version below 25. The
99 unchanged service files will not wirk correctly.
105 The udev runtime data moved from /dev/.udev/ to /run/udev/. The
106 /run mountpoint is supposed to be a tmpfs mounted during early boot,
107 available and writable to for all tools at any time during bootup,
108 it replaces /var/run/, which should become a symlink some day.
110 If /run does not exist, or is not writable, udev will fall back using
113 On systemd systems with initramfs and LVM used, packagers must
114 make sure, that the systemd and initramfs versions match. The initramfs
115 needs to create the /run mountpoint for udev to store the data, and
116 mount this tmpfs to /run in the rootfs, so the that the udev database
117 is preserved for the udev version started in the rootfs.
119 The command 'udevadm info --convert-db' is gone. The udev daemon
120 itself, at startup, converts any old database version if necessary.
122 The systemd services files have been reorganized. The udev control
123 socket is bound by systemd and passed to the started udev daemon.
124 The udev-settle.service is no longer active by default. Services which
125 can not handle hotplug setups properly need to actively pull it in, to
126 act like a barrier. Alternatively the settle service can be unconditionally
127 'systemctl'enabled, and act like a barrier for basic.target.
129 The fstab_import callout is no longer built or installed. Udev
130 should not be used to mount, does not watch changes to fstab, and
131 should not mirror fstab values in the udev database.
137 New and updated keymaps.
143 The udev database has changed, After installation of a new udev
144 version, 'udevadm info --convert-db' should be called, to let the new
145 udev/libudev version read the already stored data.
147 udevadm now supports quoting of property values, and prefixing of
149 $ udevadm info --export --export-prefix=MY_ --query=property -n sda
152 MY_DEVNAME='/dev/sda'
156 libudev now supports:
157 udev_device_get_is_initialized()
158 udev_enumerate_add_match_is_initialized()
159 to be able to skip devices the kernel has created , but udev has
162 libudev now supports:
163 udev_device_get_usec_since_initialized()
164 to retrieve the "age" of a udev device record.
166 GUdev supports a more generic GUdevEnumerator class, udev TAG
167 handling, device initialization and timestamp now.
169 The counterpart of /sys/dev/{char,block}/$major:$minor,
170 /dev/{char,block}/$major:$minor symlinks are now unconditionally
171 created, even when no rule files exist.
173 New and updated keymaps.
179 GUdev moved from /usr to /.
189 Persistent network naming rules are disabled inside of Qemu/KVM now.
191 New and updated keymaps.
193 Udev gets unconditionally enabled on systemd installations now. There
194 is no longer the need to to run 'systemctl enable udev.service'.
208 New and fixed keymaps.
210 Install systemd service files if applicable.
216 All distribution specific rules are removed from the udev source tree,
217 most of them are no longer needed. The Gentoo rules which allow to support
218 older kernel versions, which are not covered by the default rules anymore
219 has moved to rules/misc/30-kernel-compat.rules.
225 The option --debug-trace and the environemnt variable UDEVD_MAX_CHILDS=
226 was removed from udevd.
228 Udevd now checks the kernel commandline for the following variables:
229 udev.log-priority=<syslog priority>
230 udev.children-max=<maximum number of workers>
231 udev.exec-delay=<seconds to delay the execution of RUN=>
232 to help debuging coldplug setups where the loading of a kernel
233 module crashes the system.
235 The subdirectory in the source tree rules/packages has been renamed to
236 rules/arch, anc contains only architecture specific rules now.
246 Now the udev daemon itself, does on startup:
247 - copy the content of /lib/udev/devices to /dev
248 - create the standard symlinks like /dev/std{in,out,err},
249 /dev/core, /dev/fd, ...
250 - use static node information provided by kernel modules
251 and creates these nodes to allow module on-demand loading
252 - possibly apply permissions to all ststic nodes from udev
253 rules which are annotated to match a static node
255 The default mode for a device node is 0600 now to match the kernel
256 created devtmpfs defaults. If GROUP= is specified and no MODE= is
257 given the default will be 0660.
263 Udev now gradually starts to pass control over the primary device nodes
264 and their names to the kernel, and will in the end only manage the
265 permissions of the node, and possibly create additional symlinks.
266 As a first step NAME="" will be ignored, and NAME= setings with names
267 other than the kernel provided name will result in a logged warning.
268 Kernels that don't provide device names, or devtmpfs is not used, will
269 still work as they did before, but it is strongly recommended to use
270 only the same names for the primary device node as the recent kernel
271 provides for all devices.
275 Fix broken firmware loader search path.
281 "udevadm trigger" defaults to "change" events now instead of "add"
282 events. The "udev boot script" might need to add "--action=add" to
283 the trigger command if not already there, in case the initial coldplug
284 events are expected as "add" events.
286 The option "all_partitons" was removed from udev. This should not be
287 needed for usual hardware. Udev can not safely make assumptions
288 about non-existing partition major/minor numbers, and therefore no
289 longer provide this unreliable and unsafe option.
291 The option "ignore_remove" was removed from udev. With devtmpfs
292 udev passed control over device nodes to the kernel. This option
293 should not be needed, or can not work as advertised. Neither
294 udev nor the kernel will remove device nodes which are copied from
295 the /lib/udev/devices/ directory.
297 All "add|change" matches are replaced by "!remove" in the rules and
298 in the udev logic. All types of events will update possible symlinks
299 and permissions, only "remove" is handled special now.
301 The modem modeswitch extra was removed and the external usb_modeswitch
302 program should be used instead.
304 New and fixed keymaps.
314 Kernels with SYSFS_DEPRECATED=y are not supported since a while. Many users
315 depend on the current sysfs layout and the information not available in the
316 deprecated layout. All remaining support for the deprecated sysfs layout is
321 Fix for a possible endless loop in the new input_id program.
327 The option "ignore_device" does no longer exist. There is no way to
328 ignore an event, as libudev events can not be suppressed by rules.
329 It only prevented RUN keys from being executed, which results in an
330 inconsistent behavior in current setups.
332 BUS=, SYSFS{}=, ID= are long deprecated and should be SUBSYSTEM(S)=,
333 ATTR(S){}=, KERNEL(S)=. It will cause a warning once for every rule
336 The support for the deprecated IDE devices has been removed from the
337 default set of rules. Distros who still care about non-libata drivers
338 need to add the rules to the compat rules file.
340 The ID_CLASS property on input devices has been replaced by the more accurate
341 set of flags ID_INPUT_{KEYBOARD,KEY,MOUSE,TOUCHPAD,TABLET,JOYSTICK}. These are
342 determined by the new "input_id" prober now. Some devices, such as touchpads,
343 can have several classes. So if you previously had custom udev rules which e. g.
344 checked for ENV{ID_CLASS}=="kbd", you need to replace this with
345 ENV{ID_INPUT_KEYBOARD}=="?*".
351 To support DEVPATH strings larger than the maximum file name length, the
352 private udev database format has changed. If some software still reads the
353 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
354 Please do not port anything to the new format again, everything in /dev/.udev
355 is and always was private to udev, and may and will change any time without
358 Multiple devices claiming the same names in /dev are limited to symlinks
359 only now. Mixing identical symlink names and node names is not supported.
360 This reduces the amount of data in the database significantly.
362 NAME="%k" causes a warning now. It's is and always was completely superfluous.
363 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
366 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
367 if they are not the default. To support older kernels, the NAME= rules need to
368 be added to the compat rules file.
370 Symlinks to udevadm with the old command names are no longer resolved to
371 the udevadm commands.
373 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.1 is
376 The option "last_rule" does no longer exist. Its use breaks too many
377 things which expect to be run from independent later rules, and is an idication
378 that something needs to be fixed properly instead.
380 The gudev API is no longer marked as experimental,
381 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
382 is enabled by default now. Various projects already depend on introspection
383 information to bind dynamic languages to the gudev interfaces.
389 The udevadm trigger "--retry-failed" option, which is replaced since quite
390 a while by "--type=failed" is removed.
392 The failed tracking was not working at all for a few releases. The RUN
393 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
394 default is not to track any failing RUN executions.
396 New keymaps, new modem, hid2hci updated.
400 Fix possible crash in udevd when worker processes are busy, rules are
401 changed at the same time, and workers get killed to reload the rules.
407 Properties set with ENV{.FOO}="bar" are marked private by starting the
408 name with a '.'. They will not be stored in the database, and not be
409 exported with the event.
411 Firmware files are looked up in:
412 /lib/firmware/updates/$(uname -r)
413 /lib/firmware/updates
414 /lib/firmware/$(uname -r)
418 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
419 ata_id, instead of scsi_id, is the default tool now for ATA devices.
425 The configure options have changed because another library needs to be
426 installed in a different location. Instead of exec_prefix and udev_prefix,
427 libdir, rootlibdir and libexecdir are used. The Details are explained in
430 Event processes now get re-used after they handled an event. This reduces
431 the number of forks and the pressure on the CPU significantly, because
432 cloned event processes no longer cause page faults in the main daemon.
433 After the events have settled, a few worker processes stay around for
434 future events, all others get cleaned up.
436 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
437 Also inotify support is mandatory now to run udev.
439 The format of the queue exported by the udev damon has changed. There is
440 no longer a /dev/.udev/queue/ directory. The current event queue can be
441 accessed with udevadm settle and libudedv.
443 Libudev does not have the unstable API header anymore. From now on,
444 incompatible changes will be handled by bumping the library major version.
446 To build udev from the git tree gtk-doc is needed now. The tarballs will
447 build without it and contain the pre-built documentation. An online copy
449 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
451 The tools from the udev-extras repository have been merged into the main
452 udev repository. Some of the extras have larger external dependencies, and
453 they can be disabled with the configure switch --disable-extras.
459 The program vol_id and the library libvolume_id are removed from the
460 repository. Libvolume_id is merged with libblkid from the util-linux-ng
461 package. Persistent disk links for label and uuid depend on the
462 util-linux-ng version (2.15) of blkid now. Older versions of blkid
463 can not be used with udev.
465 Libudev allows to subscribe to udev events. To prevent unwanted messages
466 to be delivered, and waking up the subscribing process, a filter can be
467 installed, to drop messages inside a kernel socket filter. The filters
468 match on the <subsytem>:<devtype> properties of the device.
469 This is part of the ongoing effort to replace HAL, and switch current
470 users over to directly use libudev.
471 Libudev is still marked as experimental, and its interface might
472 eventually change if needed, but no major changes of the currently exported
473 interface are expected anymore, and a first stable release should happen
476 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
477 is not supported since while and udevd will log an error message at
478 startup. It should still be able to boot-up, but advanced rules and system
479 services which depend on the information not available in the old sysfs
480 format will fail to work correctly.
482 DVB device naming is supplied by the kernel now. In case older kernels
483 need to be supported, the old shell script should be added to a compat
490 The processed udev events get send back to the netlink socket. Libudev
491 provides access to these events. This is work-in-progress, to replace
492 the DeviceKit daemon functionality directly with libudev. There are
493 upcoming kernel changes to allow non-root users to subcribe to these
500 "udevadm settle" now optionally accepts a range of events to wait for,
501 instead of waiting for "all" events.
507 The installed watch for block device metadata changes is now removed
508 during event hadling, because some (broken) tools may be called from udev
509 rules and (wrongly) open the device with write access. After the finished
510 event handling the watch is restored.
516 Device nodes can be watched for changes with inotify with OPTIONS="watch".
517 If closed after being opened for writing, a "change" uevent will occur.
518 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
524 The udevadm test command has no longer a --force option, nodes and symlinks
525 are always updated with a test run now.
527 The udevd daemon can be started with --resolve-names=never to avoid all user
528 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
529 lookup user and groups every time events are handled.
535 We are currently merging the Ubuntu rules in the udev default rules,
536 and get one step closer to provide a common Linux /dev setup, regarding
537 device names, symlinks, and default device permissions. On udev startup,
538 we now expect the following groups to be resolvable to their ids with
540 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
541 LDAP setups need to make sure, that these groups are always resolvable at
542 bootup, with only the rootfs mounted, and without network access available.
544 Some systems may need to add some new, currently not used groups, or need
545 to add some users to new groups, but the cost of this change is minimal,
546 compared to the pain the current, rather random, differences between the
547 various distributions cause for upstream projects and third-party vendors.
549 In general, "normal" users who log into a machine should never be a member
550 of any such group, but the device-access should be managed by dynamic ACLs,
551 which get added and removed for the specific users on login/logout and
552 session activity/inactivity. These groups are only provided for custom setups,
553 and mainly system services, to allow proper privilege separation.
554 A video-streaming daemon uid would be a member of "audio" and "video", to get
555 access to the sound and video devices, but no "normal" user should ever belong
556 to the "audio" group, because he could listen to the built-in microphone with
557 any ssh-session established from the other side of the world.
559 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
560 which do not depend on the kernel device name. As usual, unique
561 devices - only a single one per product connected, or a real
562 USB serial number in the device - are always found with the same
563 name in the by-id/ directory.
564 Completely identical devices may overwrite their names in by-id/
565 and can only be found reliably in the by-path/ directory. Devices
566 specified by by-path/ must not change their connection, like the
567 USB port number they are plugged in, to keep their name.
569 To support some advanced features, Linux 2.6.22 is the oldest supported
570 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
571 supported. Older kernels should still work, and devices nodes should be
572 reliably created, but some rules and libudev will not work correctly because
573 the old kernels do not provide the expected information or interfaces.
579 Fix for a possible segfault while swapping network interface names in udev
586 The group "video" is part of the default rules now.
590 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
591 block devices in some cases. No common distro uses this option anymore,
592 and we do not get enough testing for this and recent udev versions. If
593 this option is not needed to run some old distro with a new kernel,
594 it should be disabled in the kernel config.
596 Bugfix for the $links substitution variable, which may crash if no links
597 are created. This should not happen in usual setups because we always
598 create /dev/{block,char}/ links.
600 The strings of the parsed rules, which are kept in memory, no longer
601 contain duplicate entries, or duplicate tails of strings. This, and the
602 new rules parsing/matching code reduces the total in-memory size of
603 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
606 The export of DEVTYPE=disk/partition got removed from the default
607 rules. This value is available from the kernel. The pnp shell script
608 modprobe hack is removed from the default rules. ACPI devices have _proper_
609 modalias support and take care of the same functionality.
610 Installations which support old kernels, but install current default
611 udev rules may want to add that to the compat rules file.
613 Libvolume_id now always probes for all known filesystems, and does not
614 stop at the first match. Some filesystems are marked as "exclusive probe",
615 and if any other filesytem type matches at the same time, libvolume_id
616 will, by default, not return any probing result. This is intended to prevent
617 mis-detection with conflicting left-over signatures found from earlier
618 file system formats. That way, we no longer depend on the probe-order
619 in case of multiple competing signatures. In some setups the kernel allows
620 to mount a volume with just the old filesystem signature still in place.
621 This may damage the new filesystem and cause data-loss, just by mounting
622 it. Because volume_id can not decide which one the correct signature is,
623 the wrong signatures need to be removed manually from the volume, or the
624 volume needs to be reformatted, to enable filesystem detection and possible
629 Fix segfault if compiled without optimization and dbg() does not get
630 compiled out and uses variables which are not available.
634 Bugfixes. (And maybe new bugs. :))
636 The rule matching engine got converted from a rule list to a token
637 array which reduced the in-memory rules representation of a full
638 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
639 Limits like 5 ENV and ATTR matches, and one single instance for most
640 other keys per rule are gone.
642 The NAME assignment is no longer special cased. If later rules assign
643 a NAME value again, the former value will be overwritten. As usual
644 for most other keys, the NAME value can be protected by doing a final
645 assignment with NAME:="<value>".
647 All udev code now uses libudev, which is also exported. The library
648 is still under development, marked as experimental, and its interface
649 may change as long as the DeviceKit integration is not finished.
651 Many thanks to Alan Jenkins for his continuous help, and finding and
652 optimizing some of the computing expensive parts.
658 Kernel devices and device nodes are connected now by reverse indizes in
659 /sys and /dev. A device number retrieved by a stat() or similar, the
660 kernel device directory can be found by looking up:
661 /sys/dev/{block,char}/<maj>:<min>
662 and the device node of the same device by looking up:
663 /dev/{block,char}/<maj>:<min>
667 Fix recently introduced bug, which caused a compilation without large
668 file support, where vol_id does not recognize raid signatures at the end
671 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
672 Seems some kernel versions prevent the creation of the ieee-* links,
673 so people used the scsi-* link which disappeared now.
675 More libudev work. Almost all udevadm functionality comes from libudev
678 udevadm trigger has a new option --type, which allows to trigger events
679 for "devices", for "subsystems", or "failed" devices. The old option
680 --retry-failed" still works, but is no longer mentioned in the man page.
686 The udevadm info --device-id-of-file= output has changed to use
687 the obvious format. Possible current users should use the --export
688 option which is not affected.
690 The old udev commands symlinks to udevadm are not installed, if
691 these symlinks are used, a warning is printed.
697 Optical drive's media is no longer probed for raid signatures,
698 reading the end of the device causes some devices to malfunction.
699 Also the offset of the last session found is used now to probe
702 The volume_id library got a major version number update to 1,
703 some deprecated functions are removed.
705 A shared library "libudev" gets installed now to provide access
706 to udev device information. DeviceKit, the successor of HAL, will
707 need this library to access the udev database and search sysfs for
709 The library is currently in an experimental state, also the API is
710 expected to change, as long as the DeviceKit integration is not
715 We use ./configure now. See INSTALL for details. Current
718 "/usr" - prefix for man pages, include files
720 "" - the root filesystem, prefix for libs and binaries
724 "lib" - directory name for libraries, not a path name
725 multilib 64bit systems may use "lib64" instead of "lib"
727 compile-in verbose debug messages
729 disable all logging and compile-out all log strings
731 link against SELInux libraries, to set the expected context
734 In the default rules, the group "disk" gets permissions 0660 instead
735 of 0640. One small step closer to unify distro rules. Some day, all
736 distros hopefully end up with the same set of rules.
738 No symlinks to udevadm are installed anymore, if they are still needed,
739 they should be provided by the package.
745 Default udev rules, which are not supposed to be edited by the user, should
746 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
747 the udev package and will be replaced with an update. Udev will pick up rule
749 /lib/udev/rules.d/ - default installed rules
750 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
751 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
752 It does not matter in which directory a rule file lives, all files are sorted
755 To help creating /dev/root, we have now:
756 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
759 In case the current --device-id-of-file is already used, please switch to
760 the --export format version, it saves the output parsing and the old
761 format will be changed to use ':' as a separator, like the format in the
766 Fix cdrom_id to properly recognize blank media.
772 Tape drive id-data is queried from /dev/bsg/* instead of the tape
773 nodes. This avoids rewinding tapes on open().
779 The symlinks udevcontrol and udevtrigger are no longer installed by
782 The scsi_id program does not depend on sysfs anymore. It can speak
783 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
784 data, which should solve some old problems with tape devices, where
785 we better do not open all tape device nodes to identify the device.
791 The cdrom_id program is replaced by an advanced version, which can
792 detect most common device types, and also properties of the inserted
793 media. This is part of moving some basic functionality from HAL into
794 udev (and the kernel).
800 The last WAIT_FOR_SYSFS rule is removed from the default rules.
802 The symlinks to udevadm for the debugging tools: udevmonitor and
803 udevtest are no longer created.
805 The symlinks to the udevadm man page for the old tool names are
808 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
809 should be prefixed with '@' to indicate that the path is not a
820 Udevstart is removed from the tree, it did not get installed for
821 a long time now, and is long replaced by trigger and settle.
827 All udev tools are merged into a single binary called udevadm.
828 The old names of the tools are built-in commands in udevadm now.
829 Symlinks to udevadm, with the names of the old tools, provide
830 the same functionality as the standalone tools. There is also
831 only a single udevadm.8 man page left for all tools.
833 Tools like mkinitramfs should be checked, if they need to include
834 udevadm in the list of files.
844 The etc/udev/rules.d/ directory now contains a default set of basic
845 udev rules. This initial version is the result of a rules file merge
846 of Fedora and openSUSE. For these both distros only a few specific
847 rules are left in their own file, named after the distro. Rules which
848 are optionally installed, because they are only valid for a specific
849 architecture, or rules for subsystems which are not always used are
850 in etc/udev/packages/.
856 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
857 actions by dynamically created rules.
859 SYMLINK=="<value>" matches agains the entries in the list of
860 currently defined symlinks. The links are not created in the
861 filesystem at that point in time, but the values can be matched.
863 RUN{ignore_error}+="<program>" will ignore any exit code from the
864 program and not record as a failed event.
870 Final merge of patches/features from the Ubuntu package.
876 Control characters in filesystem label strings are no longer silenty
877 removed, but hex-encoded, to be able to uniquely identify the device
878 by its symlink in /dev/disk/by-label/.
879 If libvolume_id is used by mount(8), LABEL= will work as expected,
880 if slashes or other characters are used in the label string.
882 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
883 can be specified now. The TEST key accepts an optional mode mask
884 TEST{0100}=="<is executable file>".
886 Scsi_id now supports a mode without expecting scsi-specific sysfs
887 entries to allow the extraction of cciss-device persistent properties.
893 In the future, we may see uuid's which are just simple character
894 strings (see the DDF Raid Specification). For that reason vol_id now
895 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
896 the creation of symlinks, the *_SAFE values ensure, that no control
897 or whitespace characters are used in the filename.
899 Possible users of libvolume_id, please use the volume_id_get_* functions.
900 The public struct will go away in a future release of the library.
906 Removal of useless extras/eventrecorder.sh.
916 The directory multiplexer for dev.d/ and hotplug.d are finally removed
917 from the udev package.
923 Symlinks can have priorities now, the priority is assigned to the device
924 and specified with OPTIONS="link_priority=100". Devices with higher
925 priorities overwrite the symlinks of devices with lower priorities.
926 If the device that currently owns the link, goes away, the symlink
927 will be removed, and recreated, pointing to the next device with the
928 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
929 more reliable, if multiple devices contain the same metadata and overwrite
932 The dasd_id program is removed from the udev tree, and dasdinfo, with the
933 needed rules, are part of the s390-tools now.
935 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
936 we may get the scsi sysfs mess fixed some day, and this will only catch
937 the devices we are looking for.
939 USB serial numbers for storage devices have the target:lun now appended,
940 to make it possibble to distinguish broken multi-lun devices with all
941 the same SCSI identifiers.
943 Note: The extra "run_directory" which searches and executes stuff in
944 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
945 with the next release. Make sure, that you don't use it anymore, or
946 provides your own implementation of that inefficient stuff.
947 We are tired of reports about a "slow udev", because these directories
948 contain stuff, that runs with _every_ event, instead of using rules,
949 that run programs only for the matching events.
959 DRIVER== will match only for devices that actually have a real
960 driver. DRIVERS== must be used, if parent devices should be
961 included in the match.
963 Libvolume_id's "linux_raid" detection needed another fix.
971 Add additional check to volume_id detection of via_raid, cause
972 some company decided to put a matching pattern all over the empty
973 storage area of their music players.
977 Fix path_id for SAS devices.
981 The udev daemon can be started with --debug-trace now, which will
982 execute all events serialized to get a chance to catch a possible
983 action that crashes the box.
985 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
986 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
987 are excluded from the warning. Referencing parent attributes directly
988 may break when something in the kernel driver model changes. Udev will
989 just find the attribute by walking up the parent chain.
991 Udevtrigger now sorts the list of devices depending on the device
992 dependency, so a "usb" device is triggered after the parent "pci"
997 Revert persistent-storage ata-serial '_' '-' replacement.
1003 Udevtrigger can now filter the list of devices to be triggered. Matches
1004 for subsystems or sysfs attributes can be specified.
1006 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
1007 zero-sized files to avoid pointing to /sys and confuse broken tools which
1008 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
1011 The rules and scripts to create udev rules for persistent network
1012 devices and optical drives are in the extras/rules_generator directory
1013 now. If you use something similar, please consider replacing your own
1014 version with this, to share the support effort. The rule_generator
1015 installs its own rules into /etc/udev/rules.d.
1017 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
1018 the rule_generator depends on cdrom_id to be called in an earlier rule.
1024 Renaming of some key names (the old names still work):
1025 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
1026 (The behavior of the key DRIVER will change soon in one of the next
1027 releases, to match only the event device, please switch to DRIVERS
1028 instead. If DRIVER is used, it will behave like DRIVERS, but an error
1030 With the new key names, we have a more consistent and simpler scheme.
1031 We can match the properties of the event device only, with: KERNEL,
1032 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
1033 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
1034 longer mentioned in the man page and should be switched in the rule
1037 ATTR{file}="value" can be used now, to write to a sysfs file of the
1038 event device. Instead of:
1039 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
1041 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
1043 All the PHYSDEV* keys are deprecated and will be removed from a
1045 PHYDEVPATH - is the path of a parent device and should not be
1047 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
1048 matched with SUBSYSTEMS==
1049 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
1050 Newer kernels will have DRIVER in the environment,
1051 for older kernels udev puts in. Class device will
1052 no longer carry this property of a parent and
1053 DRIVERS== can be used to match such a parent value.
1054 Note that ENV{DRIVER} is only available for a few bus devices, where
1055 the driver is already bound at device event time. On coldplug, the
1056 events for a lot devices are already bound to a driver, and they will have
1057 that value set. But on hotplug, at the time the kernel creates the device,
1058 it can't know what driver may claim the device after that, therefore
1059 in most cases it will be empty.
1061 Failed events should now be re-triggered with:
1062 udevtrigger --retry-failed.
1063 Please switch to this command, so we keep the details of the /dev/.udev/failed/
1064 files private to the udev tools. We may need to switch the current symlink
1065 target, cause some obviously broken tools try to scan all files in /dev
1066 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
1067 million times. This takes ages on slow boxes.
1069 The udevinfo attribute walk (-a) now works with giving a device node
1070 name (-n) instead of a devpath (-p). The query now always works, also when
1071 no database file was created by udev.
1073 The built-in /etc/passwd /etc/group parser is removed, we always depend on
1074 getpwnam() and getgrnam() now. One of the next releases will depend on
1075 fnmatch() and may use getopt_long().
1079 Bugfixes and small improvements.
1083 Fix path_id for recent kernels.
1089 Added support for swapping network interface names, by temporarily
1090 renaming the device and wait for the target name to become free.
1094 The built-in MODALIAS key and substitution is removed.
1098 The binary firmware helper is replaced by the usual simple
1099 shell script. Udevsend is removed from the tree.
1107 Some more keys require the correct use of '==' and '=' depending
1108 on the kind of operation beeing an assignment or a match. Rules
1109 with invalid operations are skipped and logged to syslog. Please
1110 test with udevtest if the parsing of your rules throws errors and
1111 fix possibly broken rules.
1115 Provide "udevsettle" to wait for all current udev events to finish.
1116 It also watches the current kernel netlink queue by comparing the
1117 even sequence number to make sure that there are no current pending
1118 events that have not already arrived in the daemon.
1122 Fix rule to skip persistent rules for removable IDE devices, which
1123 also skipped optical IDE drives.
1125 All *_id program are installed in /lib/udev/ by default now.
1127 No binary is stripped anymore as this should be done in the
1128 packaging process and not at build time.
1130 libvolume_id is provided as a shared library now and vol_id is
1131 linked against it. Also one of the next HAL versions will require
1132 this library, and the HAL build process will also require the
1133 header file to be installed. The copy of the same code in HAL will
1134 be removed to have only a single copy left on the system.
1138 Add persistent links for SCSI tapes. The rules file is renamed
1139 to 60-persistent-storage.rules.
1141 Create persistent path for usb devices. Can be used for all sorts
1142 of devices that can't be distinguished by other properties like
1143 multiple identical keyboards and mice connected to the same box.
1145 Provide "udevtrigger" program to request events on coldplug. The
1146 shell script is much too slow with thousends of devices.
1150 Fix persistent disk rules to exclude removable IDE drives.
1152 Warn if %e, $modalias or MODALIAS is used.
1156 Fix queue export, which wasn't correct for subsequent add/remove
1157 events for the same device.
1161 Fix cramfs detection on big endian.
1163 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
1168 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
1169 attributes were only checked at the parent device that matched the
1170 by BUS requested subsystem. Fix it to also look at the device we
1171 received the event for.
1173 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
1178 Fix a bug where NAME="" would prevent RUN from beeing executed.
1180 RUN="/bin/program" does not longer automatically add the subsystem
1181 as the first parameter. This is from the days of /sbin/hotplug
1182 which is dead now and it's just confusing to need to add a space at
1183 the end of the program name to prevent this.
1184 If you use rules that need the subsystem as the first parameter,
1185 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
1186 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
1190 The udev man page has moved to udev(7) as it does not describe a command
1191 anymore. The programs udev, udevstart and udevsend are no longer installed
1192 by default and must be copied manually, if they should be installed or
1193 included in a package.
1195 Fix a bug where "ignore_device" could run earlier collected RUN keys before
1196 the ignore rule was applied.
1198 More preparation for future sysfs changes. usb_id and scsi_id no longer
1199 depend on a magic order of devices in the /devices chain. Specific devices
1200 should be requested by their subsytem.
1202 This will always find the scsi parent device without depending on a specific
1204 dev = sysfs_device_get(devpath);
1205 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
1207 The "device" link in the current sysfs layout will be automatically
1208 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
1209 parent in the devpath. If a device is requested by it's symlink, like all
1210 class devices in the new sysfs layout will look like, it gets automatically
1211 resolved and substituted with the real devpath and not the symlink path.
1214 A similar logic must be applied to _all_ sysfs users, including
1215 scripts, that search along parent devices in sysfs. The explicit use of
1216 the "device" link must be avoided. With the future sysfs layout all
1217 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
1218 back to the "class" or the "bus". The layout of the parent devices in
1219 /devices is not necessarily expected to be stable across kernel releases and
1220 searching for parents by their subsystem should make sysfs users tolerant
1221 for changed parent chains.
1225 Prepare udev to work with the experimental kernel patch, that moves
1226 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
1228 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
1229 moving the class devices to /sys/devices.
1231 Thanks again to Marco for help finding a hopefully nice compromise
1232 to make %b simpler and working again.
1236 Complete removal of libsysfs, replaced by simple helper functions
1237 which are much simpler and a bit faster. The udev daemon operatesentirely
1238 on event parameters and does not use sysfs for simple rules anymore.
1239 Please report any new bugs/problems, that may be caused by this big
1240 change. They will be fixed immediately.
1242 The enumeration format character '%e' is deprecated and will be
1243 removed sometimes from a future udev version. It never worked correctly
1244 outside of udevstart, so we can't use it with the new parallel
1245 coldplug. A simple enumeration is as useless as the devfs naming
1246 scheme, just get rid of both if you still use it.
1248 MODALIAS and $modalias is not needed and will be removed from one of
1249 the next udev versions, replace it in all rules with ENV{MODALIAS} or
1250 the sysfs "modalias" value.
1252 Thanks a lot to Marco for all his help on finding and fixing bugs.
1256 Let scsi_id request libata drive serial numbers from page 0x80.
1258 Renamed etc/udev/persistent.rules to persistent-disk.rules and
1259 added /dev/disk/by-name/* for device mapper device names.
1261 Removed %e from the man page. It never worked reliably outside
1262 of udevstart and udevstart is no longer recommended to use.
1266 Symlinks are now exported to the event environment. Hopefully it's no
1267 longer needed to run udevinfo from an event process, like it was
1268 mentioned on the hotplug list:
1269 UDEV [1134776873.702967] add@/block/sdb
1272 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
1276 Fix a problem if udevsend is used as the hotplug handler and tries to use
1277 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
1278 and this kind of problems will hopefully go away soon.
1282 All built-in logic to work around bad sysfs timing is removed with this
1283 version. The need to wait for sysfs files is almost fixed with a kernel
1284 version that doesn't work with this udev version anyway. Until we fix
1285 the timing of the "bus" link creation, the former integrated logic should
1286 be emulated by a rule placed before all other rules:
1287 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
1289 The option "udev_db" does no longer exist. All udev state will be in
1290 /$udev_root/.udev/ now, there is no longer an option to set this
1292 If the init script or something else used this value, just depend on
1293 this hardcoded path. But remember _all_content_ of this directory is
1294 still private to udev and can change at any time.
1296 Default location for rule sripts and helper programs is now: /lib/udev/.
1297 Everything that is not useful on the commandline should go into this
1298 directory. Some of the helpers in the extras folder are installed there
1299 now. The rules need to be changed, to find the helpers there.
1301 Also /lib/udev/devices is recommended as a directory where packages or
1302 the user can place real device nodes, which get copied over to /dev at
1303 every boot. This should replace the various solutions with custom config
1306 Udevsend does no longer start the udev daemon. This must be done with
1307 the init script that prepares /dev on tmpfs and creates the initial nodes,
1308 before starting the daemon.
1312 Silent a too verbose error logging for the old hotplug.d/ dev.d/
1315 The copy of klibc is removed. A systemwide installed version of klibc
1316 should be used to build a klibc udev now.
1320 NAME="" will not create any nodes, but execute RUN keys. To completely
1321 ignore an event the OPTION "ignore_device" should be used.
1323 After removal of the reorder queue, events with a TIMEOUT can be executed
1324 without any queuing now.
1328 Fixed bug in udevd, if inotify is not available. We depend on netlink
1329 uevents now, kernels without that event source will not work with that
1330 version of udev anymore.
1334 The rule parsing happens now in the daemon once at startup, all udev
1335 event processes inherit the already parsed rules from the daemon.
1336 It is shipped with SUSE10.0 and reduces heavily the system load at
1337 startup. The option to save precompiled rules and let the udev process
1338 pick the them up is removed, as it's no longer needed.
1340 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
1341 device. Libsysfs is changed to "translate" the requested link into the
1342 real device path, as it would happen with the hotplug event. Otherwise
1343 device removal and the udev database will not work.
1345 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1348 A few improvements for vol_id, the filesytem probing code.
1352 Fix a stupid typo in extras/run_directory for "make install".
1354 scsi_id creates the temporary devnode now in /dev for usage with a
1355 non-writable /tmp directory.
1357 The uevent kernel socket buffer can carry app. 50.000 events now,
1358 let's see who can break this again. :)
1360 The upcoming kernel will have a new input driver core integration.
1361 Some class devices are now symlinks to the real device. libsysfs
1362 needs a fix for this to work correctly. Udevstart of older udev
1363 versions will _not_ create these devices!
1367 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1372 A bunch of mostly trivial bugfixes. From now on no node name or
1373 symlink name can contain any character than plain whitelisted ascii
1374 characters or validated utf8 byte-streams. This is needed for the
1375 /dev/disk/by-label/* links, because we import untrusted data and
1376 export it to the filesystem.
1380 More bugfixes. If udevd was started from the kernel, we don't
1381 have stdin/stdout/stderr, which broke the forked tools in some
1386 Bugfix. udevstart event ordering was broken for a long time.
1387 The new run_program() uncovered it, because /dev/null was not
1388 available while we try to run external programs.
1389 Now udevstart should create it before we run anything.
1393 Minor bugfixes and some distro rules updates. If you don't have the
1394 persistent disk rules in /dev/disk/by-*/* on your distro, just
1395 grab it from here. :)
1399 We can use socket communication now to pass events from udev to
1401 RUN+="socket:/org/freedesktop/hal/udev_event"
1402 will pass the whole udev event to the HAL daemon without the need
1403 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1407 Mostly bugfixes and see ChangeLog.
1409 The test for the existence of an environment value should be
1411 ENV{KEY}=="*" to ENV{KEY}=="?*"
1412 because "*" will not fail anymore, if the key does not exist or
1417 Bugfixes and a few tweaks described in the ChangeLog.
1421 Mostly a Bugfix release.
1423 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1424 timing with custom rules.
1428 We changed the internal rule storage format. Our large rule files took
1429 2 MB of RAM, with the change we are down to 99kB.
1431 If the device-node has been created with default name and no symlink or
1432 options are to remenber, it is not longer stored in the udevdb. HAL will
1433 need to be updated to work correctly with that change.
1435 To overrride optimization flags, OPTFLAGS may be used now.
1443 Major changes happened with this release. The goal is to take over the
1444 complete kernel-event handling and provide a more efficient way to dispatch
1445 kernel events. Replacing most of the current shell script logic and the
1446 kernel forked helper with a netlink-daemon and a rule-based event handling.
1448 o udevd listens to netlink events now. The first valid netlink event
1449 will make udevd ignore any message from udevsend that contains a
1450 SEQNUM, to avoid duplicate events. The forked events can be disabled
1452 echo "" > /proc/sys/kernel/hotplug
1453 For full support, the broken input-subsytem needs to be fixed, not to
1454 bypass the driver core.
1456 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1457 removed from udev itself and must be emulated by calling small
1458 helper binaries provided in the extras folder:
1459 make EXTRAS=extras/run_directory/
1460 will build udev_run_devd and udev_run_hotplugd, which can be called
1461 from a rule if needed:
1462 RUN+="/sbin/udev_run_hotplugd"
1463 The recommended way to handle this is to convert all the calls from
1464 the directories to explicit udev rules and get completely rid of the
1465 multiplexing. (To catch a ttyUSB event, you now no longer need to
1466 fork and exit 300 tty script instances you are not interested in, it
1467 is just one rule that matches exactly the device.)
1469 o udev handles now _all_ events not just events for class and block
1470 devices, this way it is possible to control the complete event
1471 behavior with udev rules. Especially useful for rules like:
1472 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1474 o As used in the modalias rule, udev supports now textual
1475 substitution placeholder along with the usual format chars. This
1476 needs to be documented, for now it's only visible in udev_rules_parse.c.
1478 o The rule keys support now more operations. This is documented in the
1479 man page. It is possible to add values to list-keys like the SYMLINK
1480 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1481 Also "final"-assignments are supported by using KEY:="value", which will
1482 prevent changing the key by any later rule.
1484 o kernel 2.6.12 has the "detached_state" attribute removed from
1485 sysfs, which was used to recognize sysfs population. We switched that
1486 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1487 Running this udev version on older kernels may cause a short delay for
1490 o To provide infrastructure for persistent device naming, the id programs:
1491 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1492 to export the probed data in environment key format:
1493 pim:~ # /sbin/ata_id --export /dev/hda
1494 ID_MODEL=HTS726060M9AT00
1495 ID_SERIAL=MRH401M4G6UM9B
1496 ID_REVISION=MH4OA6BA
1498 The following rules:
1499 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1500 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1503 kay@pim:~> tree /dev/disk
1506 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1507 | `-- IBM-Memory_Key -> ../../sda
1509 | |-- swap -> ../../hda1
1510 | |-- date -> ../../sda1
1511 | `-- home -> ../../hda3
1513 |-- 2E08712B0870F2E7 -> ../../hda3
1514 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1515 |-- E845-7A89 -> ../../sda1
1516 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1518 The IMPORT= operation will import these keys in the environment and make
1519 it available for later PROGRAM= and RUN= executed programs. The keys are
1520 also stored in the udevdb and can be queried from there with one of the
1523 o A few binaries are silently added to the repository, which can be used
1524 to replay kernel events from initramfs instead of using coldplug. udevd
1525 can be instructed now to queue-up events while the stored events from
1526 initramfs are filled into the udevd-queue. This code is still under
1527 development and there is no documentation now besides the code itself.
1528 The additional binaries get compiled, but are not installed by default.
1530 o There is also a temporary fix for a performance problem where too many
1531 events happen in parallel and every event needs to parse the rules.
1532 udev can now read precompiled rules stored on disk. This is likely to be
1533 replaced by a more elegant solution in a future udev version.
1537 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1538 Fix for libsysfs not to expect this file was added.
1542 All rules are applied now, but only the first matching rule with a NAME-key
1543 will be applied. All later rules with NAME-key are completely ignored. This
1544 way system supplied symlinks or permissions gets applied to user-defined
1548 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1549 to some rules, to keep the old behavior.
1551 The rules are read on "remove"-events too. That makes is possible to match
1552 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1553 instruct udev to ignore an event (OPTIONS="ignore_device").
1554 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1556 The new RUN-key supports rule-based execution of programs after device-node
1557 handling. This is meant as a general replacement for the dev.d/-directories
1558 to give fine grained control over the execution of programs.
1560 The %s{}-sysfs format char replacement values are searched at any of the
1561 devices in the device chain now, not only at the class-device.
1563 We support log priority levels now. The value udev_log in udev.conf is used
1564 to determine what is printed to syslog. This makes it possible to
1565 run a version with compiled-in debug messages in a production environment
1566 which is sometimes needed to find a bug.
1567 It is still possible to supress the inclusion of _any_ syslog usage with
1568 USE_LOG=false to create the smallest possible binaries if needed.
1569 The configured udev_log value can be overridden with the environment variable
1574 Possible use of a system-wide klibc:
1575 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1576 will link against an external klibc and our own version will be ignored.
1580 We support an unlimited count of symlinks now.
1582 If USE_STATIC=true is passed to a glibc build, we link statically and use
1583 a built-in userdb parser to resolve user and group names.
1585 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1586 we walk up the chain of physical devices to find a match.
1588 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1589 easy to skip certain attribute matches without composing rules with weird
1590 character class negations like:
1591 KERNEL="[!s][!c][!d]*"
1592 this can now be replaced with:
1594 The current simple '=' is still supported, and should work as it does today,
1595 but existing rules should be converted if possible, to be better readable.
1597 We have new ENV{}== key now, to match against a maximum of 5 environment
1600 udevstart is its own binary again, because we don't need co carry this araound
1601 with every forked event.