3 More libudev work. Most of udevadm's functionality comes from libudev
10 The udevadm info --device-id-of-file= output has changed to use
11 the obvious format. Possible current users should use the --export
12 option which is not affected.
14 The old udev commands symlinks to udevadm are not installed, if
15 these symlinks are used, a warning is printed.
21 Optical drive's media is no longer probed for raid signatures,
22 reading the end of the device causes some devices to malfunction.
23 Also the offset of the last session found is used now to probe
26 The volume_id library got a major version number update to 1,
27 some deprecated functions are removed.
29 A shared library "libudev" gets installed now to provide access
30 to udev device information. DeviceKit, the successor of HAL, will
31 need this library to access the udev database and search sysfs for
33 The library is currently in an experimental state, also the API is
34 expected to change, as long as the DeviceKit integration is not
39 We use ./configure now. See INSTALL for details. Current
42 "/usr" - prefix for man pages, include files
44 "" - the root filesystem, prefix for libs and binaries
48 "lib" - directory name for libraries, not a path name
49 multilib 64bit systems may use "lib64" instead of "lib"
51 compile-in verbose debug messages
53 disable all logging and compile-out all log strings
55 link against SELInux libraries, to set the expected context
58 In the default rules, the group "disk" gets permissions 0660 instead
59 of 0640. One small step closer to unify distro rules. Some day, all
60 distros hopefully end up with the same set of rules.
62 No symlinks to udevadm are installed anymore, if they are still needed,
63 they should be provided by the package.
69 Default udev rules, which are not supposed to be edited by the user, should
70 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
71 the udev package and will be replaced with an update. Udev will pick up rule
73 /lib/udev/rules.d/ - default installed rules
74 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
75 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
76 It does not matter in which directory a rule file lives, all files are sorted
79 To help creating /dev/root, we have now:
80 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
83 In case the current --device-id-of-file is already used, please switch to
84 the --export format version, it saves the output parsing and the old
85 format will be changed to use ':' as a separator, like the format in the
90 Fix cdrom_id to properly recognize blank media.
96 Tape drive id-data is queried from /dev/bsg/* instead of the tape
97 nodes. This avoids rewinding tapes on open().
103 The symlinks udevcontrol and udevtrigger are no longer installed by
106 The scsi_id program does not depend on sysfs anymore. It can speak
107 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
108 data, which should solve some old problems with tape devices, where
109 we better do not open all tape device nodes to identify the device.
115 The cdrom_id program is replaced by an advanced version, which can
116 detect most common device types, and also properties of the inserted
117 media. This is part of moving some basic functionality from HAL into
118 udev (and the kernel).
124 The last WAIT_FOR_SYSFS rule is removed from the default rules.
126 The symlinks to udevadm for the debugging tools: udevmonitor and
127 udevtest are no longer created.
129 The symlinks to the udevadm man page for the old tool names are
132 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
133 should be prefixed with '@' to indicate that the path is not a
144 Udevstart is removed from the tree, it did not get installed for
145 a long time now, and is long replaced by trigger and settle.
151 All udev tools are merged into a single binary called udevadm.
152 The old names of the tools are built-in commands in udevadm now.
153 Symlinks to udevadm, with the names of the old tools, provide
154 the same functionality as the standalone tools. There is also
155 only a single udevadm.8 man page left for all tools.
157 Tools like mkinitramfs should be checked, if they need to include
158 udevadm in the list of files.
168 The etc/udev/rules.d/ directory now contains a default set of basic
169 udev rules. This initial version is the result of a rules file merge
170 of Fedora and openSUSE. For these both distros only a few specific
171 rules are left in their own file, named after the distro. Rules which
172 are optionally installed, because they are only valid for a specific
173 architecture, or rules for subsystems which are not always used are
174 in etc/udev/packages/.
180 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
181 actions by dynamically created rules.
183 SYMLINK=="<value>" matches agains the entries in the list of
184 currently defined symlinks. The links are not created in the
185 filesystem at that point in time, but the values can be matched.
187 RUN{ignore_error}+="<program>" will ignore any exit code from the
188 program and not record as a failed event.
194 Final merge of patches/features from the Ubuntu package.
200 Control characters in filesystem label strings are no longer silenty
201 removed, but hex-encoded, to be able to uniquely identify the device
202 by its symlink in /dev/disk/by-label/.
203 If libvolume_id is used by mount(8), LABEL= will work as expected,
204 if slashes or other characters are used in the label string.
206 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
207 can be specified now. The TEST key accepts an optional mode mask
208 TEST{0100}=="<is executable file>".
210 Scsi_id now supports a mode without expecting scsi-specific sysfs
211 entries to allow the extraction of cciss-device persistent properties.
217 In the future, we may see uuid's which are just simple character
218 strings (see the DDF Raid Specification). For that reason vol_id now
219 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
220 the creation of symlinks, the *_SAFE values ensure, that no control
221 or whitespace characters are used in the filename.
223 Possible users of libvolume_id, please use the volume_id_get_* functions.
224 The public struct will go away in a future release of the library.
230 Removal of useless extras/eventrecorder.sh.
240 The directory multiplexer for dev.d/ and hotplug.d are finally removed
241 from the udev package.
247 Symlinks can have priorities now, the priority is assigned to the device
248 and specified with OPTIONS="link_priority=100". Devices with higher
249 priorities overwrite the symlinks of devices with lower priorities.
250 If the device that currently owns the link, goes away, the symlink
251 will be removed, and recreated, pointing to the next device with the
252 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
253 more reliable, if multiple devices contain the same metadata and overwrite
256 The dasd_id program is removed from the udev tree, and dasdinfo, with the
257 needed rules, are part of the s390-tools now.
259 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
260 we may get the scsi sysfs mess fixed some day, and this will only catch
261 the devices we are looking for.
263 USB serial numbers for storage devices have the target:lun now appended,
264 to make it possibble to distinguish broken multi-lun devices with all
265 the same SCSI identifiers.
267 Note: The extra "run_directory" which searches and executes stuff in
268 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
269 with the next release. Make sure, that you don't use it anymore, or
270 provides your own implementation of that inefficient stuff.
271 We are tired of reports about a "slow udev", because these directories
272 contain stuff, that runs with _every_ event, instead of using rules,
273 that run programs only for the matching events.
283 DRIVER== will match only for devices that actually have a real
284 driver. DRIVERS== must be used, if parent devices should be
285 included in the match.
287 Libvolume_id's "linux_raid" detection needed another fix.
295 Add additional check to volume_id detection of via_raid, cause
296 some company decided to put a matching pattern all over the empty
297 storage area of their music players.
301 Fix path_id for SAS devices.
305 The udev daemon can be started with --debug-trace now, which will
306 execute all events serialized to get a chance to catch a possible
307 action that crashes the box.
309 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
310 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
311 are excluded from the warning. Referencing parent attributes directly
312 may break when something in the kernel driver model changes. Udev will
313 just find the attribute by walking up the parent chain.
315 Udevtrigger now sorts the list of devices depending on the device
316 dependency, so a "usb" device is triggered after the parent "pci"
321 Revert persistent-storage ata-serial '_' '-' replacement.
327 Udevtrigger can now filter the list of devices to be triggered. Matches
328 for subsystems or sysfs attributes can be specified.
330 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
331 zero-sized files to avoid pointing to /sys and confuse broken tools which
332 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
335 The rules and scripts to create udev rules for persistent network
336 devices and optical drives are in the extras/rules_generator directory
337 now. If you use something similar, please consider replacing your own
338 version with this, to share the support effort. The rule_generator
339 installs its own rules into /etc/udev/rules.d.
341 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
342 the rule_generator depends on cdrom_id to be called in an earlier rule.
348 Renaming of some key names (the old names still work):
349 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
350 (The behavior of the key DRIVER will change soon in one of the next
351 releases, to match only the event device, please switch to DRIVERS
352 instead. If DRIVER is used, it will behave like DRIVERS, but an error
354 With the new key names, we have a more consistent and simpler scheme.
355 We can match the properties of the event device only, with: KERNEL,
356 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
357 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
358 longer mentioned in the man page and should be switched in the rule
361 ATTR{file}="value" can be used now, to write to a sysfs file of the
362 event device. Instead of:
363 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
365 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
367 All the PHYSDEV* keys are deprecated and will be removed from a
369 PHYDEVPATH - is the path of a parent device and should not be
371 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
372 matched with SUBSYSTEMS==
373 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
374 Newer kernels will have DRIVER in the environment,
375 for older kernels udev puts in. Class device will
376 no longer carry this property of a parent and
377 DRIVERS== can be used to match such a parent value.
378 Note that ENV{DRIVER} is only available for a few bus devices, where
379 the driver is already bound at device event time. On coldplug, the
380 events for a lot devices are already bound to a driver, and they will have
381 that value set. But on hotplug, at the time the kernel creates the device,
382 it can't know what driver may claim the device after that, therefore
383 in most cases it will be empty.
385 Failed events should now be re-triggered with:
386 udevtrigger --retry-failed.
387 Please switch to this command, so we keep the details of the /dev/.udev/failed/
388 files private to the udev tools. We may need to switch the current symlink
389 target, cause some obviously broken tools try to scan all files in /dev
390 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
391 million times. This takes ages on slow boxes.
393 The udevinfo attribute walk (-a) now works with giving a device node
394 name (-n) instead of a devpath (-p). The query now always works, also when
395 no database file was created by udev.
397 The built-in /etc/passwd /etc/group parser is removed, we always depend on
398 getpwnam() and getgrnam() now. One of the next releases will depend on
399 fnmatch() and may use getopt_long().
403 Bugfixes and small improvements.
407 Fix path_id for recent kernels.
413 Added support for swapping network interface names, by temporarily
414 renaming the device and wait for the target name to become free.
418 The built-in MODALIAS key and substitution is removed.
422 The binary firmware helper is replaced by the usual simple
423 shell script. Udevsend is removed from the tree.
431 Some more keys require the correct use of '==' and '=' depending
432 on the kind of operation beeing an assignment or a match. Rules
433 with invalid operations are skipped and logged to syslog. Please
434 test with udevtest if the parsing of your rules throws errors and
435 fix possibly broken rules.
439 Provide "udevsettle" to wait for all current udev events to finish.
440 It also watches the current kernel netlink queue by comparing the
441 even sequence number to make sure that there are no current pending
442 events that have not already arrived in the daemon.
446 Fix rule to skip persistent rules for removable IDE devices, which
447 also skipped optical IDE drives.
449 All *_id program are installed in /lib/udev/ by default now.
451 No binary is stripped anymore as this should be done in the
452 packaging process and not at build time.
454 libvolume_id is provided as a shared library now and vol_id is
455 linked against it. Also one of the next HAL versions will require
456 this library, and the HAL build process will also require the
457 header file to be installed. The copy of the same code in HAL will
458 be removed to have only a single copy left on the system.
462 Add persistent links for SCSI tapes. The rules file is renamed
463 to 60-persistent-storage.rules.
465 Create persistent path for usb devices. Can be used for all sorts
466 of devices that can't be distinguished by other properties like
467 multiple identical keyboards and mice connected to the same box.
469 Provide "udevtrigger" program to request events on coldplug. The
470 shell script is much too slow with thousends of devices.
474 Fix persistent disk rules to exclude removable IDE drives.
476 Warn if %e, $modalias or MODALIAS is used.
480 Fix queue export, which wasn't correct for subsequent add/remove
481 events for the same device.
485 Fix cramfs detection on big endian.
487 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
492 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
493 attributes were only checked at the parent device that matched the
494 by BUS requested subsystem. Fix it to also look at the device we
495 received the event for.
497 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
502 Fix a bug where NAME="" would prevent RUN from beeing executed.
504 RUN="/bin/program" does not longer automatically add the subsystem
505 as the first parameter. This is from the days of /sbin/hotplug
506 which is dead now and it's just confusing to need to add a space at
507 the end of the program name to prevent this.
508 If you use rules that need the subsystem as the first parameter,
509 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
510 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
514 The udev man page has moved to udev(7) as it does not describe a command
515 anymore. The programs udev, udevstart and udevsend are no longer installed
516 by default and must be copied manually, if they should be installed or
517 included in a package.
519 Fix a bug where "ignore_device" could run earlier collected RUN keys before
520 the ignore rule was applied.
522 More preparation for future sysfs changes. usb_id and scsi_id no longer
523 depend on a magic order of devices in the /devices chain. Specific devices
524 should be requested by their subsytem.
526 This will always find the scsi parent device without depending on a specific
528 dev = sysfs_device_get(devpath);
529 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
531 The "device" link in the current sysfs layout will be automatically
532 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
533 parent in the devpath. If a device is requested by it's symlink, like all
534 class devices in the new sysfs layout will look like, it gets automatically
535 resolved and substituted with the real devpath and not the symlink path.
538 A similar logic must be applied to _all_ sysfs users, including
539 scripts, that search along parent devices in sysfs. The explicit use of
540 the "device" link must be avoided. With the future sysfs layout all
541 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
542 back to the "class" or the "bus". The layout of the parent devices in
543 /devices is not necessarily expected to be stable across kernel releases and
544 searching for parents by their subsystem should make sysfs users tolerant
545 for changed parent chains.
549 Prepare udev to work with the experimental kernel patch, that moves
550 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
552 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
553 moving the class devices to /sys/devices.
555 Thanks again to Marco for help finding a hopefully nice compromise
556 to make %b simpler and working again.
560 Complete removal of libsysfs, replaced by simple helper functions
561 which are much simpler and a bit faster. The udev daemon operatesentirely
562 on event parameters and does not use sysfs for simple rules anymore.
563 Please report any new bugs/problems, that may be caused by this big
564 change. They will be fixed immediately.
566 The enumeration format character '%e' is deprecated and will be
567 removed sometimes from a future udev version. It never worked correctly
568 outside of udevstart, so we can't use it with the new parallel
569 coldplug. A simple enumeration is as useless as the devfs naming
570 scheme, just get rid of both if you still use it.
572 MODALIAS and $modalias is not needed and will be removed from one of
573 the next udev versions, replace it in all rules with ENV{MODALIAS} or
574 the sysfs "modalias" value.
576 Thanks a lot to Marco for all his help on finding and fixing bugs.
580 Let scsi_id request libata drive serial numbers from page 0x80.
582 Renamed etc/udev/persistent.rules to persistent-disk.rules and
583 added /dev/disk/by-name/* for device mapper device names.
585 Removed %e from the man page. It never worked reliably outside
586 of udevstart and udevstart is no longer recommended to use.
590 Symlinks are now exported to the event environment. Hopefully it's no
591 longer needed to run udevinfo from an event process, like it was
592 mentioned on the hotplug list:
593 UDEV [1134776873.702967] add@/block/sdb
596 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
600 Fix a problem if udevsend is used as the hotplug handler and tries to use
601 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
602 and this kind of problems will hopefully go away soon.
606 All built-in logic to work around bad sysfs timing is removed with this
607 version. The need to wait for sysfs files is almost fixed with a kernel
608 version that doesn't work with this udev version anyway. Until we fix
609 the timing of the "bus" link creation, the former integrated logic should
610 be emulated by a rule placed before all other rules:
611 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
613 The option "udev_db" does no longer exist. All udev state will be in
614 /$udev_root/.udev/ now, there is no longer an option to set this
616 If the init script or something else used this value, just depend on
617 this hardcoded path. But remember _all_content_ of this directory is
618 still private to udev and can change at any time.
620 Default location for rule sripts and helper programs is now: /lib/udev/.
621 Everything that is not useful on the commandline should go into this
622 directory. Some of the helpers in the extras folder are installed there
623 now. The rules need to be changed, to find the helpers there.
625 Also /lib/udev/devices is recommended as a directory where packages or
626 the user can place real device nodes, which get copied over to /dev at
627 every boot. This should replace the various solutions with custom config
630 Udevsend does no longer start the udev daemon. This must be done with
631 the init script that prepares /dev on tmpfs and creates the initial nodes,
632 before starting the daemon.
636 Silent a too verbose error logging for the old hotplug.d/ dev.d/
639 The copy of klibc is removed. A systemwide installed version of klibc
640 should be used to build a klibc udev now.
644 NAME="" will not create any nodes, but execute RUN keys. To completely
645 ignore an event the OPTION "ignore_device" should be used.
647 After removal of the reorder queue, events with a TIMEOUT can be executed
648 without any queuing now.
652 Fixed bug in udevd, if inotify is not available. We depend on netlink
653 uevents now, kernels without that event source will not work with that
654 version of udev anymore.
658 The rule parsing happens now in the daemon once at startup, all udev
659 event processes inherit the already parsed rules from the daemon.
660 It is shipped with SUSE10.0 and reduces heavily the system load at
661 startup. The option to save precompiled rules and let the udev process
662 pick the them up is removed, as it's no longer needed.
664 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
665 device. Libsysfs is changed to "translate" the requested link into the
666 real device path, as it would happen with the hotplug event. Otherwise
667 device removal and the udev database will not work.
669 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
672 A few improvements for vol_id, the filesytem probing code.
676 Fix a stupid typo in extras/run_directory for "make install".
678 scsi_id creates the temporary devnode now in /dev for usage with a
679 non-writable /tmp directory.
681 The uevent kernel socket buffer can carry app. 50.000 events now,
682 let's see who can break this again. :)
684 The upcoming kernel will have a new input driver core integration.
685 Some class devices are now symlinks to the real device. libsysfs
686 needs a fix for this to work correctly. Udevstart of older udev
687 versions will _not_ create these devices!
691 Fix a 'install' target in the Makefile, that prevents EXTRAS from
696 A bunch of mostly trivial bugfixes. From now on no node name or
697 symlink name can contain any character than plain whitelisted ascii
698 characters or validated utf8 byte-streams. This is needed for the
699 /dev/disk/by-label/* links, because we import untrusted data and
700 export it to the filesystem.
704 More bugfixes. If udevd was started from the kernel, we don't
705 have stdin/stdout/stderr, which broke the forked tools in some
710 Bugfix. udevstart event ordering was broken for a long time.
711 The new run_program() uncovered it, because /dev/null was not
712 available while we try to run external programs.
713 Now udevstart should create it before we run anything.
717 Minor bugfixes and some distro rules updates. If you don't have the
718 persistent disk rules in /dev/disk/by-*/* on your distro, just
719 grab it from here. :)
723 We can use socket communication now to pass events from udev to
725 RUN+="socket:/org/freedesktop/hal/udev_event"
726 will pass the whole udev event to the HAL daemon without the need
727 for a forked helper. (See ChangeLog for udevmonitor, as an example)
731 Mostly bugfixes and see ChangeLog.
733 The test for the existence of an environment value should be
735 ENV{KEY}=="*" to ENV{KEY}=="?*"
736 because "*" will not fail anymore, if the key does not exist or
741 Bugfixes and a few tweaks described in the ChangeLog.
745 Mostly a Bugfix release.
747 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
748 timing with custom rules.
752 We changed the internal rule storage format. Our large rule files took
753 2 MB of RAM, with the change we are down to 99kB.
755 If the device-node has been created with default name and no symlink or
756 options are to remenber, it is not longer stored in the udevdb. HAL will
757 need to be updated to work correctly with that change.
759 To overrride optimization flags, OPTFLAGS may be used now.
767 Major changes happened with this release. The goal is to take over the
768 complete kernel-event handling and provide a more efficient way to dispatch
769 kernel events. Replacing most of the current shell script logic and the
770 kernel forked helper with a netlink-daemon and a rule-based event handling.
772 o udevd listens to netlink events now. The first valid netlink event
773 will make udevd ignore any message from udevsend that contains a
774 SEQNUM, to avoid duplicate events. The forked events can be disabled
776 echo "" > /proc/sys/kernel/hotplug
777 For full support, the broken input-subsytem needs to be fixed, not to
778 bypass the driver core.
780 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
781 removed from udev itself and must be emulated by calling small
782 helper binaries provided in the extras folder:
783 make EXTRAS=extras/run_directory/
784 will build udev_run_devd and udev_run_hotplugd, which can be called
785 from a rule if needed:
786 RUN+="/sbin/udev_run_hotplugd"
787 The recommended way to handle this is to convert all the calls from
788 the directories to explicit udev rules and get completely rid of the
789 multiplexing. (To catch a ttyUSB event, you now no longer need to
790 fork and exit 300 tty script instances you are not interested in, it
791 is just one rule that matches exactly the device.)
793 o udev handles now _all_ events not just events for class and block
794 devices, this way it is possible to control the complete event
795 behavior with udev rules. Especially useful for rules like:
796 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
798 o As used in the modalias rule, udev supports now textual
799 substitution placeholder along with the usual format chars. This
800 needs to be documented, for now it's only visible in udev_rules_parse.c.
802 o The rule keys support now more operations. This is documented in the
803 man page. It is possible to add values to list-keys like the SYMLINK
804 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
805 Also "final"-assignments are supported by using KEY:="value", which will
806 prevent changing the key by any later rule.
808 o kernel 2.6.12 has the "detached_state" attribute removed from
809 sysfs, which was used to recognize sysfs population. We switched that
810 to wait for the "bus" link, which is only available in kernels after 2.6.11.
811 Running this udev version on older kernels may cause a short delay for
814 o To provide infrastructure for persistent device naming, the id programs:
815 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
816 to export the probed data in environment key format:
817 pim:~ # /sbin/ata_id --export /dev/hda
818 ID_MODEL=HTS726060M9AT00
819 ID_SERIAL=MRH401M4G6UM9B
823 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
824 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
827 kay@pim:~> tree /dev/disk
830 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
831 | `-- IBM-Memory_Key -> ../../sda
833 | |-- swap -> ../../hda1
834 | |-- date -> ../../sda1
835 | `-- home -> ../../hda3
837 |-- 2E08712B0870F2E7 -> ../../hda3
838 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
839 |-- E845-7A89 -> ../../sda1
840 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
842 The IMPORT= operation will import these keys in the environment and make
843 it available for later PROGRAM= and RUN= executed programs. The keys are
844 also stored in the udevdb and can be queried from there with one of the
847 o A few binaries are silently added to the repository, which can be used
848 to replay kernel events from initramfs instead of using coldplug. udevd
849 can be instructed now to queue-up events while the stored events from
850 initramfs are filled into the udevd-queue. This code is still under
851 development and there is no documentation now besides the code itself.
852 The additional binaries get compiled, but are not installed by default.
854 o There is also a temporary fix for a performance problem where too many
855 events happen in parallel and every event needs to parse the rules.
856 udev can now read precompiled rules stored on disk. This is likely to be
857 replaced by a more elegant solution in a future udev version.
861 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
862 Fix for libsysfs not to expect this file was added.
866 All rules are applied now, but only the first matching rule with a NAME-key
867 will be applied. All later rules with NAME-key are completely ignored. This
868 way system supplied symlinks or permissions gets applied to user-defined
872 Please check your rules setup, if you may need to add OPTIONS="last_rule"
873 to some rules, to keep the old behavior.
875 The rules are read on "remove"-events too. That makes is possible to match
876 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
877 instruct udev to ignore an event (OPTIONS="ignore_device").
878 The new ACTION-key may be used to let a rule act only at a "remove"-event.
880 The new RUN-key supports rule-based execution of programs after device-node
881 handling. This is meant as a general replacement for the dev.d/-directories
882 to give fine grained control over the execution of programs.
884 The %s{}-sysfs format char replacement values are searched at any of the
885 devices in the device chain now, not only at the class-device.
887 We support log priority levels now. The value udev_log in udev.conf is used
888 to determine what is printed to syslog. This makes it possible to
889 run a version with compiled-in debug messages in a production environment
890 which is sometimes needed to find a bug.
891 It is still possible to supress the inclusion of _any_ syslog usage with
892 USE_LOG=false to create the smallest possible binaries if needed.
893 The configured udev_log value can be overridden with the environment variable
898 Possible use of a system-wide klibc:
899 make USE_KLIBC=true KLCC=/usr/bin/klcc all
900 will link against an external klibc and our own version will be ignored.
904 We support an unlimited count of symlinks now.
906 If USE_STATIC=true is passed to a glibc build, we link statically and use
907 a built-in userdb parser to resolve user and group names.
909 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
910 we walk up the chain of physical devices to find a match.
912 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
913 easy to skip certain attribute matches without composing rules with weird
914 character class negations like:
915 KERNEL="[!s][!c][!d]*"
916 this can now be replaced with:
918 The current simple '=' is still supported, and should work as it does today,
919 but existing rules should be converted if possible, to be better readable.
921 We have new ENV{}== key now, to match against a maximum of 5 environment
924 udevstart is its own binary again, because we don't need co carry this araound
925 with every forked event.