3 We use ./configure now. See INSTALL for details. Current
6 "/usr" - prefix for man pages, include files
8 "" - the root filesystem, prefix for libs and binaries
12 "lib" - directory name for libraries, not a path name
13 multilib 64bit systems may use "lib64" instead of "lib"
15 compile-in verbose debug messages
17 disable all logging and compile-out all log strings
19 link against SELInux libraries to set the expected context
22 No symlinks to udevadm are installed anymore, if still neded, the
23 package should create them.
29 Default udev rules, which are not supposed to be edited by the user, should
30 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
31 the udev package and will be replaced with an update. Udev will pick up rule
33 /lib/udev/rules.d/ - default installed rules
34 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
35 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
36 It does not matter in which directory a rule file lives, all files are sorted
39 To help creating /dev/root, we have now:
40 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
43 In case the current --device-id-of-file is already used, please switch to
44 the --export format version, it saves the output parsing and the old
45 format will be changed to use ':' as a separator, like the format in the
50 Fix cdrom_id to properly recognize blank media.
56 Tape drive id-data is queried from /dev/bsg/* instead of the tape
57 nodes. This avoids rewinding tapes on open().
63 The symlinks udevcontrol and udevtrigger are no longer installed by
66 The scsi_id program does not depend on sysfs anymore. It can speak
67 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
68 data, which should solve some old problems with tape devices, where
69 we better do not open all tape device nodes to identify the device.
75 The cdrom_id program is replaced by an advanced version, which can
76 detect most common device types, and also properties of the inserted
77 media. This is part of moving some basic functionality from HAL into
78 udev (and the kernel).
84 The last WAIT_FOR_SYSFS rule is removed from the default rules.
86 The symlinks to udevadm for the debugging tools: udevmonitor and
87 udevtest are no longer created.
89 The symlinks to the udevadm man page for the old tool names are
92 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
93 should be prefixed with '@' to indicate that the path is not a
104 Udevstart is removed from the tree, it did not get installed for
105 a long time now, and is long replaced by trigger and settle.
111 All udev tools are merged into a single binary called udevadm.
112 The old names of the tools are built-in commands in udevadm now.
113 Symlinks to udevadm, with the names of the old tools, provide
114 the same functionality as the standalone tools. There is also
115 only a single udevadm.8 man page left for all tools.
117 Tools like mkinitramfs should be checked, if they need to include
118 udevadm in the list of files.
128 The etc/udev/rules.d/ directory now contains a default set of basic
129 udev rules. This initial version is the result of a rules file merge
130 of Fedora and openSUSE. For these both distros only a few specific
131 rules are left in their own file, named after the distro. Rules which
132 are optionally installed, because they are only valid for a specific
133 architecture, or rules for subsystems which are not always used are
134 in etc/udev/packages/.
140 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
141 actions by dynamically created rules.
143 SYMLINK=="<value>" matches agains the entries in the list of
144 currently defined symlinks. The links are not created in the
145 filesystem at that point in time, but the values can be matched.
147 RUN{ignore_error}+="<program>" will ignore any exit code from the
148 program and not record as a failed event.
154 Final merge of patches/features from the Ubuntu package.
160 Control characters in filesystem label strings are no longer silenty
161 removed, but hex-encoded, to be able to uniquely identify the device
162 by its symlink in /dev/disk/by-label/.
163 If libvolume_id is used by mount(8), LABEL= will work as expected,
164 if slashes or other characters are used in the label string.
166 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
167 can be specified now. The TEST key accepts an optional mode mask
168 TEST{0100}=="<is executable file>".
170 Scsi_id now supports a mode without expecting scsi-specific sysfs
171 entries to allow the extraction of cciss-device persistent properties.
177 In the future, we may see uuid's which are just simple character
178 strings (see the DDF Raid Specification). For that reason vol_id now
179 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
180 the creation of symlinks, the *_SAFE values ensure, that no control
181 or whitespace characters are used in the filename.
183 Possible users of libvolume_id, please use the volume_id_get_* functions.
184 The public struct will go away in a future release of the library.
190 Removal of useless extras/eventrecorder.sh.
200 The directory multiplexer for dev.d/ and hotplug.d are finally removed
201 from the udev package.
207 Symlinks can have priorities now, the priority is assigned to the device
208 and specified with OPTIONS="link_priority=100". Devices with higher
209 priorities overwrite the symlinks of devices with lower priorities.
210 If the device that currently owns the link, goes away, the symlink
211 will be removed, and recreated, pointing to the next device with the
212 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
213 more reliable, if multiple devices contain the same metadata and overwrite
216 The dasd_id program is removed from the udev tree, and dasdinfo, with the
217 needed rules, are part of the s390-tools now.
219 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
220 we may get the scsi sysfs mess fixed some day, and this will only catch
221 the devices we are looking for.
223 USB serial numbers for storage devices have the target:lun now appended,
224 to make it possibble to distinguish broken multi-lun devices with all
225 the same SCSI identifiers.
227 Note: The extra "run_directory" which searches and executes stuff in
228 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
229 with the next release. Make sure, that you don't use it anymore, or
230 provides your own implementation of that inefficient stuff.
231 We are tired of reports about a "slow udev", because these directories
232 contain stuff, that runs with _every_ event, instead of using rules,
233 that run programs only for the matching events.
243 DRIVER== will match only for devices that actually have a real
244 driver. DRIVERS== must be used, if parent devices should be
245 included in the match.
247 Libvolume_id's "linux_raid" detection needed another fix.
255 Add additional check to volume_id detection of via_raid, cause
256 some company decided to put a matching pattern all over the empty
257 storage area of their music players.
261 Fix path_id for SAS devices.
265 The udev daemon can be started with --debug-trace now, which will
266 execute all events serialized to get a chance to catch a possible
267 action that crashes the box.
269 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
270 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
271 are excluded from the warning. Referencing parent attributes directly
272 may break when something in the kernel driver model changes. Udev will
273 just find the attribute by walking up the parent chain.
275 Udevtrigger now sorts the list of devices depending on the device
276 dependency, so a "usb" device is triggered after the parent "pci"
281 Revert persistent-storage ata-serial '_' '-' replacement.
287 Udevtrigger can now filter the list of devices to be triggered. Matches
288 for subsystems or sysfs attributes can be specified.
290 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
291 zero-sized files to avoid pointing to /sys and confuse broken tools which
292 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
295 The rules and scripts to create udev rules for persistent network
296 devices and optical drives are in the extras/rules_generator directory
297 now. If you use something similar, please consider replacing your own
298 version with this, to share the support effort. The rule_generator
299 installs its own rules into /etc/udev/rules.d.
301 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
302 the rule_generator depends on cdrom_id to be called in an earlier rule.
308 Renaming of some key names (the old names still work):
309 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
310 (The behavior of the key DRIVER will change soon in one of the next
311 releases, to match only the event device, please switch to DRIVERS
312 instead. If DRIVER is used, it will behave like DRIVERS, but an error
314 With the new key names, we have a more consistent and simpler scheme.
315 We can match the properties of the event device only, with: KERNEL,
316 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
317 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
318 longer mentioned in the man page and should be switched in the rule
321 ATTR{file}="value" can be used now, to write to a sysfs file of the
322 event device. Instead of:
323 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
325 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
327 All the PHYSDEV* keys are deprecated and will be removed from a
329 PHYDEVPATH - is the path of a parent device and should not be
331 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
332 matched with SUBSYSTEMS==
333 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
334 Newer kernels will have DRIVER in the environment,
335 for older kernels udev puts in. Class device will
336 no longer carry this property of a parent and
337 DRIVERS== can be used to match such a parent value.
338 Note that ENV{DRIVER} is only available for a few bus devices, where
339 the driver is already bound at device event time. On coldplug, the
340 events for a lot devices are already bound to a driver, and they will have
341 that value set. But on hotplug, at the time the kernel creates the device,
342 it can't know what driver may claim the device after that, therefore
343 in most cases it will be empty.
345 Failed events should now be re-triggered with:
346 udevtrigger --retry-failed.
347 Please switch to this command, so we keep the details of the /dev/.udev/failed/
348 files private to the udev tools. We may need to switch the current symlink
349 target, cause some obviously broken tools try to scan all files in /dev
350 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
351 million times. This takes ages on slow boxes.
353 The udevinfo attribute walk (-a) now works with giving a device node
354 name (-n) instead of a devpath (-p). The query now always works, also when
355 no database file was created by udev.
357 The built-in /etc/passwd /etc/group parser is removed, we always depend on
358 getpwnam() and getgrnam() now. One of the next releases will depend on
359 fnmatch() and may use getopt_long().
363 Bugfixes and small improvements.
367 Fix path_id for recent kernels.
373 Added support for swapping network interface names, by temporarily
374 renaming the device and wait for the target name to become free.
378 The built-in MODALIAS key and substitution is removed.
382 The binary firmware helper is replaced by the usual simple
383 shell script. Udevsend is removed from the tree.
391 Some more keys require the correct use of '==' and '=' depending
392 on the kind of operation beeing an assignment or a match. Rules
393 with invalid operations are skipped and logged to syslog. Please
394 test with udevtest if the parsing of your rules throws errors and
395 fix possibly broken rules.
399 Provide "udevsettle" to wait for all current udev events to finish.
400 It also watches the current kernel netlink queue by comparing the
401 even sequence number to make sure that there are no current pending
402 events that have not already arrived in the daemon.
406 Fix rule to skip persistent rules for removable IDE devices, which
407 also skipped optical IDE drives.
409 All *_id program are installed in /lib/udev/ by default now.
411 No binary is stripped anymore as this should be done in the
412 packaging process and not at build time.
414 libvolume_id is provided as a shared library now and vol_id is
415 linked against it. Also one of the next HAL versions will require
416 this library, and the HAL build process will also require the
417 header file to be installed. The copy of the same code in HAL will
418 be removed to have only a single copy left on the system.
422 Add persistent links for SCSI tapes. The rules file is renamed
423 to 60-persistent-storage.rules.
425 Create persistent path for usb devices. Can be used for all sorts
426 of devices that can't be distinguished by other properties like
427 multiple identical keyboards and mice connected to the same box.
429 Provide "udevtrigger" program to request events on coldplug. The
430 shell script is much too slow with thousends of devices.
434 Fix persistent disk rules to exclude removable IDE drives.
436 Warn if %e, $modalias or MODALIAS is used.
440 Fix queue export, which wasn't correct for subsequent add/remove
441 events for the same device.
445 Fix cramfs detection on big endian.
447 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
452 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
453 attributes were only checked at the parent device that matched the
454 by BUS requested subsystem. Fix it to also look at the device we
455 received the event for.
457 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
462 Fix a bug where NAME="" would prevent RUN from beeing executed.
464 RUN="/bin/program" does not longer automatically add the subsystem
465 as the first parameter. This is from the days of /sbin/hotplug
466 which is dead now and it's just confusing to need to add a space at
467 the end of the program name to prevent this.
468 If you use rules that need the subsystem as the first parameter,
469 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
470 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
474 The udev man page has moved to udev(7) as it does not describe a command
475 anymore. The programs udev, udevstart and udevsend are no longer installed
476 by default and must be copied manually, if they should be installed or
477 included in a package.
479 Fix a bug where "ignore_device" could run earlier collected RUN keys before
480 the ignore rule was applied.
482 More preparation for future sysfs changes. usb_id and scsi_id no longer
483 depend on a magic order of devices in the /devices chain. Specific devices
484 should be requested by their subsytem.
486 This will always find the scsi parent device without depending on a specific
488 dev = sysfs_device_get(devpath);
489 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
491 The "device" link in the current sysfs layout will be automatically
492 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
493 parent in the devpath. If a device is requested by it's symlink, like all
494 class devices in the new sysfs layout will look like, it gets automatically
495 resolved and substituted with the real devpath and not the symlink path.
498 A similar logic must be applied to _all_ sysfs users, including
499 scripts, that search along parent devices in sysfs. The explicit use of
500 the "device" link must be avoided. With the future sysfs layout all
501 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
502 back to the "class" or the "bus". The layout of the parent devices in
503 /devices is not necessarily expected to be stable across kernel releases and
504 searching for parents by their subsystem should make sysfs users tolerant
505 for changed parent chains.
509 Prepare udev to work with the experimental kernel patch, that moves
510 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
512 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
513 moving the class devices to /sys/devices.
515 Thanks again to Marco for help finding a hopefully nice compromise
516 to make %b simpler and working again.
520 Complete removal of libsysfs, replaced by simple helper functions
521 which are much simpler and a bit faster. The udev daemon operatesentirely
522 on event parameters and does not use sysfs for simple rules anymore.
523 Please report any new bugs/problems, that may be caused by this big
524 change. They will be fixed immediately.
526 The enumeration format character '%e' is deprecated and will be
527 removed sometimes from a future udev version. It never worked correctly
528 outside of udevstart, so we can't use it with the new parallel
529 coldplug. A simple enumeration is as useless as the devfs naming
530 scheme, just get rid of both if you still use it.
532 MODALIAS and $modalias is not needed and will be removed from one of
533 the next udev versions, replace it in all rules with ENV{MODALIAS} or
534 the sysfs "modalias" value.
536 Thanks a lot to Marco for all his help on finding and fixing bugs.
540 Let scsi_id request libata drive serial numbers from page 0x80.
542 Renamed etc/udev/persistent.rules to persistent-disk.rules and
543 added /dev/disk/by-name/* for device mapper device names.
545 Removed %e from the man page. It never worked reliably outside
546 of udevstart and udevstart is no longer recommended to use.
550 Symlinks are now exported to the event environment. Hopefully it's no
551 longer needed to run udevinfo from an event process, like it was
552 mentioned on the hotplug list:
553 UDEV [1134776873.702967] add@/block/sdb
556 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
560 Fix a problem if udevsend is used as the hotplug handler and tries to use
561 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
562 and this kind of problems will hopefully go away soon.
566 All built-in logic to work around bad sysfs timing is removed with this
567 version. The need to wait for sysfs files is almost fixed with a kernel
568 version that doesn't work with this udev version anyway. Until we fix
569 the timing of the "bus" link creation, the former integrated logic should
570 be emulated by a rule placed before all other rules:
571 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
573 The option "udev_db" does no longer exist. All udev state will be in
574 /$udev_root/.udev/ now, there is no longer an option to set this
576 If the init script or something else used this value, just depend on
577 this hardcoded path. But remember _all_content_ of this directory is
578 still private to udev and can change at any time.
580 Default location for rule sripts and helper programs is now: /lib/udev/.
581 Everything that is not useful on the commandline should go into this
582 directory. Some of the helpers in the extras folder are installed there
583 now. The rules need to be changed, to find the helpers there.
585 Also /lib/udev/devices is recommended as a directory where packages or
586 the user can place real device nodes, which get copied over to /dev at
587 every boot. This should replace the various solutions with custom config
590 Udevsend does no longer start the udev daemon. This must be done with
591 the init script that prepares /dev on tmpfs and creates the initial nodes,
592 before starting the daemon.
596 Silent a too verbose error logging for the old hotplug.d/ dev.d/
599 The copy of klibc is removed. A systemwide installed version of klibc
600 should be used to build a klibc udev now.
604 NAME="" will not create any nodes, but execute RUN keys. To completely
605 ignore an event the OPTION "ignore_device" should be used.
607 After removal of the reorder queue, events with a TIMEOUT can be executed
608 without any queuing now.
612 Fixed bug in udevd, if inotify is not available. We depend on netlink
613 uevents now, kernels without that event source will not work with that
614 version of udev anymore.
618 The rule parsing happens now in the daemon once at startup, all udev
619 event processes inherit the already parsed rules from the daemon.
620 It is shipped with SUSE10.0 and reduces heavily the system load at
621 startup. The option to save precompiled rules and let the udev process
622 pick the them up is removed, as it's no longer needed.
624 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
625 device. Libsysfs is changed to "translate" the requested link into the
626 real device path, as it would happen with the hotplug event. Otherwise
627 device removal and the udev database will not work.
629 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
632 A few improvements for vol_id, the filesytem probing code.
636 Fix a stupid typo in extras/run_directory for "make install".
638 scsi_id creates the temporary devnode now in /dev for usage with a
639 non-writable /tmp directory.
641 The uevent kernel socket buffer can carry app. 50.000 events now,
642 let's see who can break this again. :)
644 The upcoming kernel will have a new input driver core integration.
645 Some class devices are now symlinks to the real device. libsysfs
646 needs a fix for this to work correctly. Udevstart of older udev
647 versions will _not_ create these devices!
651 Fix a 'install' target in the Makefile, that prevents EXTRAS from
656 A bunch of mostly trivial bugfixes. From now on no node name or
657 symlink name can contain any character than plain whitelisted ascii
658 characters or validated utf8 byte-streams. This is needed for the
659 /dev/disk/by-label/* links, because we import untrusted data and
660 export it to the filesystem.
664 More bugfixes. If udevd was started from the kernel, we don't
665 have stdin/stdout/stderr, which broke the forked tools in some
670 Bugfix. udevstart event ordering was broken for a long time.
671 The new run_program() uncovered it, because /dev/null was not
672 available while we try to run external programs.
673 Now udevstart should create it before we run anything.
677 Minor bugfixes and some distro rules updates. If you don't have the
678 persistent disk rules in /dev/disk/by-*/* on your distro, just
679 grab it from here. :)
683 We can use socket communication now to pass events from udev to
685 RUN+="socket:/org/freedesktop/hal/udev_event"
686 will pass the whole udev event to the HAL daemon without the need
687 for a forked helper. (See ChangeLog for udevmonitor, as an example)
691 Mostly bugfixes and see ChangeLog.
693 The test for the existence of an environment value should be
695 ENV{KEY}=="*" to ENV{KEY}=="?*"
696 because "*" will not fail anymore, if the key does not exist or
701 Bugfixes and a few tweaks described in the ChangeLog.
705 Mostly a Bugfix release.
707 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
708 timing with custom rules.
712 We changed the internal rule storage format. Our large rule files took
713 2 MB of RAM, with the change we are down to 99kB.
715 If the device-node has been created with default name and no symlink or
716 options are to remenber, it is not longer stored in the udevdb. HAL will
717 need to be updated to work correctly with that change.
719 To overrride optimization flags, OPTFLAGS may be used now.
727 Major changes happened with this release. The goal is to take over the
728 complete kernel-event handling and provide a more efficient way to dispatch
729 kernel events. Replacing most of the current shell script logic and the
730 kernel forked helper with a netlink-daemon and a rule-based event handling.
732 o udevd listens to netlink events now. The first valid netlink event
733 will make udevd ignore any message from udevsend that contains a
734 SEQNUM, to avoid duplicate events. The forked events can be disabled
736 echo "" > /proc/sys/kernel/hotplug
737 For full support, the broken input-subsytem needs to be fixed, not to
738 bypass the driver core.
740 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
741 removed from udev itself and must be emulated by calling small
742 helper binaries provided in the extras folder:
743 make EXTRAS=extras/run_directory/
744 will build udev_run_devd and udev_run_hotplugd, which can be called
745 from a rule if needed:
746 RUN+="/sbin/udev_run_hotplugd"
747 The recommended way to handle this is to convert all the calls from
748 the directories to explicit udev rules and get completely rid of the
749 multiplexing. (To catch a ttyUSB event, you now no longer need to
750 fork and exit 300 tty script instances you are not interested in, it
751 is just one rule that matches exactly the device.)
753 o udev handles now _all_ events not just events for class and block
754 devices, this way it is possible to control the complete event
755 behavior with udev rules. Especially useful for rules like:
756 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
758 o As used in the modalias rule, udev supports now textual
759 substitution placeholder along with the usual format chars. This
760 needs to be documented, for now it's only visible in udev_rules_parse.c.
762 o The rule keys support now more operations. This is documented in the
763 man page. It is possible to add values to list-keys like the SYMLINK
764 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
765 Also "final"-assignments are supported by using KEY:="value", which will
766 prevent changing the key by any later rule.
768 o kernel 2.6.12 has the "detached_state" attribute removed from
769 sysfs, which was used to recognize sysfs population. We switched that
770 to wait for the "bus" link, which is only available in kernels after 2.6.11.
771 Running this udev version on older kernels may cause a short delay for
774 o To provide infrastructure for persistent device naming, the id programs:
775 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
776 to export the probed data in environment key format:
777 pim:~ # /sbin/ata_id --export /dev/hda
778 ID_MODEL=HTS726060M9AT00
779 ID_SERIAL=MRH401M4G6UM9B
783 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
784 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
787 kay@pim:~> tree /dev/disk
790 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
791 | `-- IBM-Memory_Key -> ../../sda
793 | |-- swap -> ../../hda1
794 | |-- date -> ../../sda1
795 | `-- home -> ../../hda3
797 |-- 2E08712B0870F2E7 -> ../../hda3
798 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
799 |-- E845-7A89 -> ../../sda1
800 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
802 The IMPORT= operation will import these keys in the environment and make
803 it available for later PROGRAM= and RUN= executed programs. The keys are
804 also stored in the udevdb and can be queried from there with one of the
807 o A few binaries are silently added to the repository, which can be used
808 to replay kernel events from initramfs instead of using coldplug. udevd
809 can be instructed now to queue-up events while the stored events from
810 initramfs are filled into the udevd-queue. This code is still under
811 development and there is no documentation now besides the code itself.
812 The additional binaries get compiled, but are not installed by default.
814 o There is also a temporary fix for a performance problem where too many
815 events happen in parallel and every event needs to parse the rules.
816 udev can now read precompiled rules stored on disk. This is likely to be
817 replaced by a more elegant solution in a future udev version.
821 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
822 Fix for libsysfs not to expect this file was added.
826 All rules are applied now, but only the first matching rule with a NAME-key
827 will be applied. All later rules with NAME-key are completely ignored. This
828 way system supplied symlinks or permissions gets applied to user-defined
832 Please check your rules setup, if you may need to add OPTIONS="last_rule"
833 to some rules, to keep the old behavior.
835 The rules are read on "remove"-events too. That makes is possible to match
836 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
837 instruct udev to ignore an event (OPTIONS="ignore_device").
838 The new ACTION-key may be used to let a rule act only at a "remove"-event.
840 The new RUN-key supports rule-based execution of programs after device-node
841 handling. This is meant as a general replacement for the dev.d/-directories
842 to give fine grained control over the execution of programs.
844 The %s{}-sysfs format char replacement values are searched at any of the
845 devices in the device chain now, not only at the class-device.
847 We support log priority levels now. The value udev_log in udev.conf is used
848 to determine what is printed to syslog. This makes it possible to
849 run a version with compiled-in debug messages in a production environment
850 which is sometimes needed to find a bug.
851 It is still possible to supress the inclusion of _any_ syslog usage with
852 USE_LOG=false to create the smallest possible binaries if needed.
853 The configured udev_log value can be overridden with the environment variable
858 Possible use of a system-wide klibc:
859 make USE_KLIBC=true KLCC=/usr/bin/klcc all
860 will link against an external klibc and our own version will be ignored.
864 We support an unlimited count of symlinks now.
866 If USE_STATIC=true is passed to a glibc build, we link statically and use
867 a built-in userdb parser to resolve user and group names.
869 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
870 we walk up the chain of physical devices to find a match.
872 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
873 easy to skip certain attribute matches without composing rules with weird
874 character class negations like:
875 KERNEL="[!s][!c][!d]*"
876 this can now be replaced with:
878 The current simple '=' is still supported, and should work as it does today,
879 but existing rules should be converted if possible, to be better readable.
881 We have new ENV{}== key now, to match against a maximum of 5 environment
884 udevstart is its own binary again, because we don't need co carry this araound
885 with every forked event.