9 Kernel devices and device nodes are connected now by reverse indizes in
10 /sys and /dev. A device number retrieved by a stat() or similar, the
11 kernel device directory can be found by looking up:
12 /sys/dev/{block,char}/<maj>:<min>
13 and the device node of the same device by looking up:
14 /dev/{block,char}/<maj>:<min>
18 Fix recently introduced bug, which caused a compilation without large
19 file support, where vol_id does not recognize raid signatures at the end
22 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
23 Seems some kernel versions prevent the creation of the ieee-* links,
24 so people used the scsi-* link which disappeared now.
26 More libudev work. Almost all udevadm functionality comes from libudev
29 udevadm trigger has a new option --type, which allows to trigger events
30 for "devices", for "subsystems", or "failed" devices. The old option
31 --retry-failed" still works, but is no longer mentioned in the man page.
37 The udevadm info --device-id-of-file= output has changed to use
38 the obvious format. Possible current users should use the --export
39 option which is not affected.
41 The old udev commands symlinks to udevadm are not installed, if
42 these symlinks are used, a warning is printed.
48 Optical drive's media is no longer probed for raid signatures,
49 reading the end of the device causes some devices to malfunction.
50 Also the offset of the last session found is used now to probe
53 The volume_id library got a major version number update to 1,
54 some deprecated functions are removed.
56 A shared library "libudev" gets installed now to provide access
57 to udev device information. DeviceKit, the successor of HAL, will
58 need this library to access the udev database and search sysfs for
60 The library is currently in an experimental state, also the API is
61 expected to change, as long as the DeviceKit integration is not
66 We use ./configure now. See INSTALL for details. Current
69 "/usr" - prefix for man pages, include files
71 "" - the root filesystem, prefix for libs and binaries
75 "lib" - directory name for libraries, not a path name
76 multilib 64bit systems may use "lib64" instead of "lib"
78 compile-in verbose debug messages
80 disable all logging and compile-out all log strings
82 link against SELInux libraries, to set the expected context
85 In the default rules, the group "disk" gets permissions 0660 instead
86 of 0640. One small step closer to unify distro rules. Some day, all
87 distros hopefully end up with the same set of rules.
89 No symlinks to udevadm are installed anymore, if they are still needed,
90 they should be provided by the package.
96 Default udev rules, which are not supposed to be edited by the user, should
97 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
98 the udev package and will be replaced with an update. Udev will pick up rule
100 /lib/udev/rules.d/ - default installed rules
101 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
102 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
103 It does not matter in which directory a rule file lives, all files are sorted
106 To help creating /dev/root, we have now:
107 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
110 In case the current --device-id-of-file is already used, please switch to
111 the --export format version, it saves the output parsing and the old
112 format will be changed to use ':' as a separator, like the format in the
117 Fix cdrom_id to properly recognize blank media.
123 Tape drive id-data is queried from /dev/bsg/* instead of the tape
124 nodes. This avoids rewinding tapes on open().
130 The symlinks udevcontrol and udevtrigger are no longer installed by
133 The scsi_id program does not depend on sysfs anymore. It can speak
134 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
135 data, which should solve some old problems with tape devices, where
136 we better do not open all tape device nodes to identify the device.
142 The cdrom_id program is replaced by an advanced version, which can
143 detect most common device types, and also properties of the inserted
144 media. This is part of moving some basic functionality from HAL into
145 udev (and the kernel).
151 The last WAIT_FOR_SYSFS rule is removed from the default rules.
153 The symlinks to udevadm for the debugging tools: udevmonitor and
154 udevtest are no longer created.
156 The symlinks to the udevadm man page for the old tool names are
159 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
160 should be prefixed with '@' to indicate that the path is not a
171 Udevstart is removed from the tree, it did not get installed for
172 a long time now, and is long replaced by trigger and settle.
178 All udev tools are merged into a single binary called udevadm.
179 The old names of the tools are built-in commands in udevadm now.
180 Symlinks to udevadm, with the names of the old tools, provide
181 the same functionality as the standalone tools. There is also
182 only a single udevadm.8 man page left for all tools.
184 Tools like mkinitramfs should be checked, if they need to include
185 udevadm in the list of files.
195 The etc/udev/rules.d/ directory now contains a default set of basic
196 udev rules. This initial version is the result of a rules file merge
197 of Fedora and openSUSE. For these both distros only a few specific
198 rules are left in their own file, named after the distro. Rules which
199 are optionally installed, because they are only valid for a specific
200 architecture, or rules for subsystems which are not always used are
201 in etc/udev/packages/.
207 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
208 actions by dynamically created rules.
210 SYMLINK=="<value>" matches agains the entries in the list of
211 currently defined symlinks. The links are not created in the
212 filesystem at that point in time, but the values can be matched.
214 RUN{ignore_error}+="<program>" will ignore any exit code from the
215 program and not record as a failed event.
221 Final merge of patches/features from the Ubuntu package.
227 Control characters in filesystem label strings are no longer silenty
228 removed, but hex-encoded, to be able to uniquely identify the device
229 by its symlink in /dev/disk/by-label/.
230 If libvolume_id is used by mount(8), LABEL= will work as expected,
231 if slashes or other characters are used in the label string.
233 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
234 can be specified now. The TEST key accepts an optional mode mask
235 TEST{0100}=="<is executable file>".
237 Scsi_id now supports a mode without expecting scsi-specific sysfs
238 entries to allow the extraction of cciss-device persistent properties.
244 In the future, we may see uuid's which are just simple character
245 strings (see the DDF Raid Specification). For that reason vol_id now
246 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
247 the creation of symlinks, the *_SAFE values ensure, that no control
248 or whitespace characters are used in the filename.
250 Possible users of libvolume_id, please use the volume_id_get_* functions.
251 The public struct will go away in a future release of the library.
257 Removal of useless extras/eventrecorder.sh.
267 The directory multiplexer for dev.d/ and hotplug.d are finally removed
268 from the udev package.
274 Symlinks can have priorities now, the priority is assigned to the device
275 and specified with OPTIONS="link_priority=100". Devices with higher
276 priorities overwrite the symlinks of devices with lower priorities.
277 If the device that currently owns the link, goes away, the symlink
278 will be removed, and recreated, pointing to the next device with the
279 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
280 more reliable, if multiple devices contain the same metadata and overwrite
283 The dasd_id program is removed from the udev tree, and dasdinfo, with the
284 needed rules, are part of the s390-tools now.
286 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
287 we may get the scsi sysfs mess fixed some day, and this will only catch
288 the devices we are looking for.
290 USB serial numbers for storage devices have the target:lun now appended,
291 to make it possibble to distinguish broken multi-lun devices with all
292 the same SCSI identifiers.
294 Note: The extra "run_directory" which searches and executes stuff in
295 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
296 with the next release. Make sure, that you don't use it anymore, or
297 provides your own implementation of that inefficient stuff.
298 We are tired of reports about a "slow udev", because these directories
299 contain stuff, that runs with _every_ event, instead of using rules,
300 that run programs only for the matching events.
310 DRIVER== will match only for devices that actually have a real
311 driver. DRIVERS== must be used, if parent devices should be
312 included in the match.
314 Libvolume_id's "linux_raid" detection needed another fix.
322 Add additional check to volume_id detection of via_raid, cause
323 some company decided to put a matching pattern all over the empty
324 storage area of their music players.
328 Fix path_id for SAS devices.
332 The udev daemon can be started with --debug-trace now, which will
333 execute all events serialized to get a chance to catch a possible
334 action that crashes the box.
336 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
337 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
338 are excluded from the warning. Referencing parent attributes directly
339 may break when something in the kernel driver model changes. Udev will
340 just find the attribute by walking up the parent chain.
342 Udevtrigger now sorts the list of devices depending on the device
343 dependency, so a "usb" device is triggered after the parent "pci"
348 Revert persistent-storage ata-serial '_' '-' replacement.
354 Udevtrigger can now filter the list of devices to be triggered. Matches
355 for subsystems or sysfs attributes can be specified.
357 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
358 zero-sized files to avoid pointing to /sys and confuse broken tools which
359 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
362 The rules and scripts to create udev rules for persistent network
363 devices and optical drives are in the extras/rules_generator directory
364 now. If you use something similar, please consider replacing your own
365 version with this, to share the support effort. The rule_generator
366 installs its own rules into /etc/udev/rules.d.
368 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
369 the rule_generator depends on cdrom_id to be called in an earlier rule.
375 Renaming of some key names (the old names still work):
376 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
377 (The behavior of the key DRIVER will change soon in one of the next
378 releases, to match only the event device, please switch to DRIVERS
379 instead. If DRIVER is used, it will behave like DRIVERS, but an error
381 With the new key names, we have a more consistent and simpler scheme.
382 We can match the properties of the event device only, with: KERNEL,
383 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
384 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
385 longer mentioned in the man page and should be switched in the rule
388 ATTR{file}="value" can be used now, to write to a sysfs file of the
389 event device. Instead of:
390 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
392 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
394 All the PHYSDEV* keys are deprecated and will be removed from a
396 PHYDEVPATH - is the path of a parent device and should not be
398 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
399 matched with SUBSYSTEMS==
400 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
401 Newer kernels will have DRIVER in the environment,
402 for older kernels udev puts in. Class device will
403 no longer carry this property of a parent and
404 DRIVERS== can be used to match such a parent value.
405 Note that ENV{DRIVER} is only available for a few bus devices, where
406 the driver is already bound at device event time. On coldplug, the
407 events for a lot devices are already bound to a driver, and they will have
408 that value set. But on hotplug, at the time the kernel creates the device,
409 it can't know what driver may claim the device after that, therefore
410 in most cases it will be empty.
412 Failed events should now be re-triggered with:
413 udevtrigger --retry-failed.
414 Please switch to this command, so we keep the details of the /dev/.udev/failed/
415 files private to the udev tools. We may need to switch the current symlink
416 target, cause some obviously broken tools try to scan all files in /dev
417 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
418 million times. This takes ages on slow boxes.
420 The udevinfo attribute walk (-a) now works with giving a device node
421 name (-n) instead of a devpath (-p). The query now always works, also when
422 no database file was created by udev.
424 The built-in /etc/passwd /etc/group parser is removed, we always depend on
425 getpwnam() and getgrnam() now. One of the next releases will depend on
426 fnmatch() and may use getopt_long().
430 Bugfixes and small improvements.
434 Fix path_id for recent kernels.
440 Added support for swapping network interface names, by temporarily
441 renaming the device and wait for the target name to become free.
445 The built-in MODALIAS key and substitution is removed.
449 The binary firmware helper is replaced by the usual simple
450 shell script. Udevsend is removed from the tree.
458 Some more keys require the correct use of '==' and '=' depending
459 on the kind of operation beeing an assignment or a match. Rules
460 with invalid operations are skipped and logged to syslog. Please
461 test with udevtest if the parsing of your rules throws errors and
462 fix possibly broken rules.
466 Provide "udevsettle" to wait for all current udev events to finish.
467 It also watches the current kernel netlink queue by comparing the
468 even sequence number to make sure that there are no current pending
469 events that have not already arrived in the daemon.
473 Fix rule to skip persistent rules for removable IDE devices, which
474 also skipped optical IDE drives.
476 All *_id program are installed in /lib/udev/ by default now.
478 No binary is stripped anymore as this should be done in the
479 packaging process and not at build time.
481 libvolume_id is provided as a shared library now and vol_id is
482 linked against it. Also one of the next HAL versions will require
483 this library, and the HAL build process will also require the
484 header file to be installed. The copy of the same code in HAL will
485 be removed to have only a single copy left on the system.
489 Add persistent links for SCSI tapes. The rules file is renamed
490 to 60-persistent-storage.rules.
492 Create persistent path for usb devices. Can be used for all sorts
493 of devices that can't be distinguished by other properties like
494 multiple identical keyboards and mice connected to the same box.
496 Provide "udevtrigger" program to request events on coldplug. The
497 shell script is much too slow with thousends of devices.
501 Fix persistent disk rules to exclude removable IDE drives.
503 Warn if %e, $modalias or MODALIAS is used.
507 Fix queue export, which wasn't correct for subsequent add/remove
508 events for the same device.
512 Fix cramfs detection on big endian.
514 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
519 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
520 attributes were only checked at the parent device that matched the
521 by BUS requested subsystem. Fix it to also look at the device we
522 received the event for.
524 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
529 Fix a bug where NAME="" would prevent RUN from beeing executed.
531 RUN="/bin/program" does not longer automatically add the subsystem
532 as the first parameter. This is from the days of /sbin/hotplug
533 which is dead now and it's just confusing to need to add a space at
534 the end of the program name to prevent this.
535 If you use rules that need the subsystem as the first parameter,
536 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
537 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
541 The udev man page has moved to udev(7) as it does not describe a command
542 anymore. The programs udev, udevstart and udevsend are no longer installed
543 by default and must be copied manually, if they should be installed or
544 included in a package.
546 Fix a bug where "ignore_device" could run earlier collected RUN keys before
547 the ignore rule was applied.
549 More preparation for future sysfs changes. usb_id and scsi_id no longer
550 depend on a magic order of devices in the /devices chain. Specific devices
551 should be requested by their subsytem.
553 This will always find the scsi parent device without depending on a specific
555 dev = sysfs_device_get(devpath);
556 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
558 The "device" link in the current sysfs layout will be automatically
559 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
560 parent in the devpath. If a device is requested by it's symlink, like all
561 class devices in the new sysfs layout will look like, it gets automatically
562 resolved and substituted with the real devpath and not the symlink path.
565 A similar logic must be applied to _all_ sysfs users, including
566 scripts, that search along parent devices in sysfs. The explicit use of
567 the "device" link must be avoided. With the future sysfs layout all
568 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
569 back to the "class" or the "bus". The layout of the parent devices in
570 /devices is not necessarily expected to be stable across kernel releases and
571 searching for parents by their subsystem should make sysfs users tolerant
572 for changed parent chains.
576 Prepare udev to work with the experimental kernel patch, that moves
577 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
579 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
580 moving the class devices to /sys/devices.
582 Thanks again to Marco for help finding a hopefully nice compromise
583 to make %b simpler and working again.
587 Complete removal of libsysfs, replaced by simple helper functions
588 which are much simpler and a bit faster. The udev daemon operatesentirely
589 on event parameters and does not use sysfs for simple rules anymore.
590 Please report any new bugs/problems, that may be caused by this big
591 change. They will be fixed immediately.
593 The enumeration format character '%e' is deprecated and will be
594 removed sometimes from a future udev version. It never worked correctly
595 outside of udevstart, so we can't use it with the new parallel
596 coldplug. A simple enumeration is as useless as the devfs naming
597 scheme, just get rid of both if you still use it.
599 MODALIAS and $modalias is not needed and will be removed from one of
600 the next udev versions, replace it in all rules with ENV{MODALIAS} or
601 the sysfs "modalias" value.
603 Thanks a lot to Marco for all his help on finding and fixing bugs.
607 Let scsi_id request libata drive serial numbers from page 0x80.
609 Renamed etc/udev/persistent.rules to persistent-disk.rules and
610 added /dev/disk/by-name/* for device mapper device names.
612 Removed %e from the man page. It never worked reliably outside
613 of udevstart and udevstart is no longer recommended to use.
617 Symlinks are now exported to the event environment. Hopefully it's no
618 longer needed to run udevinfo from an event process, like it was
619 mentioned on the hotplug list:
620 UDEV [1134776873.702967] add@/block/sdb
623 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
627 Fix a problem if udevsend is used as the hotplug handler and tries to use
628 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
629 and this kind of problems will hopefully go away soon.
633 All built-in logic to work around bad sysfs timing is removed with this
634 version. The need to wait for sysfs files is almost fixed with a kernel
635 version that doesn't work with this udev version anyway. Until we fix
636 the timing of the "bus" link creation, the former integrated logic should
637 be emulated by a rule placed before all other rules:
638 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
640 The option "udev_db" does no longer exist. All udev state will be in
641 /$udev_root/.udev/ now, there is no longer an option to set this
643 If the init script or something else used this value, just depend on
644 this hardcoded path. But remember _all_content_ of this directory is
645 still private to udev and can change at any time.
647 Default location for rule sripts and helper programs is now: /lib/udev/.
648 Everything that is not useful on the commandline should go into this
649 directory. Some of the helpers in the extras folder are installed there
650 now. The rules need to be changed, to find the helpers there.
652 Also /lib/udev/devices is recommended as a directory where packages or
653 the user can place real device nodes, which get copied over to /dev at
654 every boot. This should replace the various solutions with custom config
657 Udevsend does no longer start the udev daemon. This must be done with
658 the init script that prepares /dev on tmpfs and creates the initial nodes,
659 before starting the daemon.
663 Silent a too verbose error logging for the old hotplug.d/ dev.d/
666 The copy of klibc is removed. A systemwide installed version of klibc
667 should be used to build a klibc udev now.
671 NAME="" will not create any nodes, but execute RUN keys. To completely
672 ignore an event the OPTION "ignore_device" should be used.
674 After removal of the reorder queue, events with a TIMEOUT can be executed
675 without any queuing now.
679 Fixed bug in udevd, if inotify is not available. We depend on netlink
680 uevents now, kernels without that event source will not work with that
681 version of udev anymore.
685 The rule parsing happens now in the daemon once at startup, all udev
686 event processes inherit the already parsed rules from the daemon.
687 It is shipped with SUSE10.0 and reduces heavily the system load at
688 startup. The option to save precompiled rules and let the udev process
689 pick the them up is removed, as it's no longer needed.
691 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
692 device. Libsysfs is changed to "translate" the requested link into the
693 real device path, as it would happen with the hotplug event. Otherwise
694 device removal and the udev database will not work.
696 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
699 A few improvements for vol_id, the filesytem probing code.
703 Fix a stupid typo in extras/run_directory for "make install".
705 scsi_id creates the temporary devnode now in /dev for usage with a
706 non-writable /tmp directory.
708 The uevent kernel socket buffer can carry app. 50.000 events now,
709 let's see who can break this again. :)
711 The upcoming kernel will have a new input driver core integration.
712 Some class devices are now symlinks to the real device. libsysfs
713 needs a fix for this to work correctly. Udevstart of older udev
714 versions will _not_ create these devices!
718 Fix a 'install' target in the Makefile, that prevents EXTRAS from
723 A bunch of mostly trivial bugfixes. From now on no node name or
724 symlink name can contain any character than plain whitelisted ascii
725 characters or validated utf8 byte-streams. This is needed for the
726 /dev/disk/by-label/* links, because we import untrusted data and
727 export it to the filesystem.
731 More bugfixes. If udevd was started from the kernel, we don't
732 have stdin/stdout/stderr, which broke the forked tools in some
737 Bugfix. udevstart event ordering was broken for a long time.
738 The new run_program() uncovered it, because /dev/null was not
739 available while we try to run external programs.
740 Now udevstart should create it before we run anything.
744 Minor bugfixes and some distro rules updates. If you don't have the
745 persistent disk rules in /dev/disk/by-*/* on your distro, just
746 grab it from here. :)
750 We can use socket communication now to pass events from udev to
752 RUN+="socket:/org/freedesktop/hal/udev_event"
753 will pass the whole udev event to the HAL daemon without the need
754 for a forked helper. (See ChangeLog for udevmonitor, as an example)
758 Mostly bugfixes and see ChangeLog.
760 The test for the existence of an environment value should be
762 ENV{KEY}=="*" to ENV{KEY}=="?*"
763 because "*" will not fail anymore, if the key does not exist or
768 Bugfixes and a few tweaks described in the ChangeLog.
772 Mostly a Bugfix release.
774 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
775 timing with custom rules.
779 We changed the internal rule storage format. Our large rule files took
780 2 MB of RAM, with the change we are down to 99kB.
782 If the device-node has been created with default name and no symlink or
783 options are to remenber, it is not longer stored in the udevdb. HAL will
784 need to be updated to work correctly with that change.
786 To overrride optimization flags, OPTFLAGS may be used now.
794 Major changes happened with this release. The goal is to take over the
795 complete kernel-event handling and provide a more efficient way to dispatch
796 kernel events. Replacing most of the current shell script logic and the
797 kernel forked helper with a netlink-daemon and a rule-based event handling.
799 o udevd listens to netlink events now. The first valid netlink event
800 will make udevd ignore any message from udevsend that contains a
801 SEQNUM, to avoid duplicate events. The forked events can be disabled
803 echo "" > /proc/sys/kernel/hotplug
804 For full support, the broken input-subsytem needs to be fixed, not to
805 bypass the driver core.
807 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
808 removed from udev itself and must be emulated by calling small
809 helper binaries provided in the extras folder:
810 make EXTRAS=extras/run_directory/
811 will build udev_run_devd and udev_run_hotplugd, which can be called
812 from a rule if needed:
813 RUN+="/sbin/udev_run_hotplugd"
814 The recommended way to handle this is to convert all the calls from
815 the directories to explicit udev rules and get completely rid of the
816 multiplexing. (To catch a ttyUSB event, you now no longer need to
817 fork and exit 300 tty script instances you are not interested in, it
818 is just one rule that matches exactly the device.)
820 o udev handles now _all_ events not just events for class and block
821 devices, this way it is possible to control the complete event
822 behavior with udev rules. Especially useful for rules like:
823 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
825 o As used in the modalias rule, udev supports now textual
826 substitution placeholder along with the usual format chars. This
827 needs to be documented, for now it's only visible in udev_rules_parse.c.
829 o The rule keys support now more operations. This is documented in the
830 man page. It is possible to add values to list-keys like the SYMLINK
831 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
832 Also "final"-assignments are supported by using KEY:="value", which will
833 prevent changing the key by any later rule.
835 o kernel 2.6.12 has the "detached_state" attribute removed from
836 sysfs, which was used to recognize sysfs population. We switched that
837 to wait for the "bus" link, which is only available in kernels after 2.6.11.
838 Running this udev version on older kernels may cause a short delay for
841 o To provide infrastructure for persistent device naming, the id programs:
842 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
843 to export the probed data in environment key format:
844 pim:~ # /sbin/ata_id --export /dev/hda
845 ID_MODEL=HTS726060M9AT00
846 ID_SERIAL=MRH401M4G6UM9B
850 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
851 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
854 kay@pim:~> tree /dev/disk
857 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
858 | `-- IBM-Memory_Key -> ../../sda
860 | |-- swap -> ../../hda1
861 | |-- date -> ../../sda1
862 | `-- home -> ../../hda3
864 |-- 2E08712B0870F2E7 -> ../../hda3
865 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
866 |-- E845-7A89 -> ../../sda1
867 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
869 The IMPORT= operation will import these keys in the environment and make
870 it available for later PROGRAM= and RUN= executed programs. The keys are
871 also stored in the udevdb and can be queried from there with one of the
874 o A few binaries are silently added to the repository, which can be used
875 to replay kernel events from initramfs instead of using coldplug. udevd
876 can be instructed now to queue-up events while the stored events from
877 initramfs are filled into the udevd-queue. This code is still under
878 development and there is no documentation now besides the code itself.
879 The additional binaries get compiled, but are not installed by default.
881 o There is also a temporary fix for a performance problem where too many
882 events happen in parallel and every event needs to parse the rules.
883 udev can now read precompiled rules stored on disk. This is likely to be
884 replaced by a more elegant solution in a future udev version.
888 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
889 Fix for libsysfs not to expect this file was added.
893 All rules are applied now, but only the first matching rule with a NAME-key
894 will be applied. All later rules with NAME-key are completely ignored. This
895 way system supplied symlinks or permissions gets applied to user-defined
899 Please check your rules setup, if you may need to add OPTIONS="last_rule"
900 to some rules, to keep the old behavior.
902 The rules are read on "remove"-events too. That makes is possible to match
903 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
904 instruct udev to ignore an event (OPTIONS="ignore_device").
905 The new ACTION-key may be used to let a rule act only at a "remove"-event.
907 The new RUN-key supports rule-based execution of programs after device-node
908 handling. This is meant as a general replacement for the dev.d/-directories
909 to give fine grained control over the execution of programs.
911 The %s{}-sysfs format char replacement values are searched at any of the
912 devices in the device chain now, not only at the class-device.
914 We support log priority levels now. The value udev_log in udev.conf is used
915 to determine what is printed to syslog. This makes it possible to
916 run a version with compiled-in debug messages in a production environment
917 which is sometimes needed to find a bug.
918 It is still possible to supress the inclusion of _any_ syslog usage with
919 USE_LOG=false to create the smallest possible binaries if needed.
920 The configured udev_log value can be overridden with the environment variable
925 Possible use of a system-wide klibc:
926 make USE_KLIBC=true KLCC=/usr/bin/klcc all
927 will link against an external klibc and our own version will be ignored.
931 We support an unlimited count of symlinks now.
933 If USE_STATIC=true is passed to a glibc build, we link statically and use
934 a built-in userdb parser to resolve user and group names.
936 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
937 we walk up the chain of physical devices to find a match.
939 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
940 easy to skip certain attribute matches without composing rules with weird
941 character class negations like:
942 KERNEL="[!s][!c][!d]*"
943 this can now be replaced with:
945 The current simple '=' is still supported, and should work as it does today,
946 but existing rules should be converted if possible, to be better readable.
948 We have new ENV{}== key now, to match against a maximum of 5 environment
951 udevstart is its own binary again, because we don't need co carry this araound
952 with every forked event.