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 In the default rules, the group "disk" gets permissions 0660 instead
23 of 0640. One small step closer to unify distro rules. Some day, all
24 distros hopefully end up with the same set of rules.
26 No symlinks to udevadm are installed anymore, if they are still needed,
27 they should be provided by the package.
33 Default udev rules, which are not supposed to be edited by the user, should
34 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
35 the udev package and will be replaced with an update. Udev will pick up rule
37 /lib/udev/rules.d/ - default installed rules
38 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
39 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
40 It does not matter in which directory a rule file lives, all files are sorted
43 To help creating /dev/root, we have now:
44 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
47 In case the current --device-id-of-file is already used, please switch to
48 the --export format version, it saves the output parsing and the old
49 format will be changed to use ':' as a separator, like the format in the
54 Fix cdrom_id to properly recognize blank media.
60 Tape drive id-data is queried from /dev/bsg/* instead of the tape
61 nodes. This avoids rewinding tapes on open().
67 The symlinks udevcontrol and udevtrigger are no longer installed by
70 The scsi_id program does not depend on sysfs anymore. It can speak
71 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
72 data, which should solve some old problems with tape devices, where
73 we better do not open all tape device nodes to identify the device.
79 The cdrom_id program is replaced by an advanced version, which can
80 detect most common device types, and also properties of the inserted
81 media. This is part of moving some basic functionality from HAL into
82 udev (and the kernel).
88 The last WAIT_FOR_SYSFS rule is removed from the default rules.
90 The symlinks to udevadm for the debugging tools: udevmonitor and
91 udevtest are no longer created.
93 The symlinks to the udevadm man page for the old tool names are
96 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
97 should be prefixed with '@' to indicate that the path is not a
108 Udevstart is removed from the tree, it did not get installed for
109 a long time now, and is long replaced by trigger and settle.
115 All udev tools are merged into a single binary called udevadm.
116 The old names of the tools are built-in commands in udevadm now.
117 Symlinks to udevadm, with the names of the old tools, provide
118 the same functionality as the standalone tools. There is also
119 only a single udevadm.8 man page left for all tools.
121 Tools like mkinitramfs should be checked, if they need to include
122 udevadm in the list of files.
132 The etc/udev/rules.d/ directory now contains a default set of basic
133 udev rules. This initial version is the result of a rules file merge
134 of Fedora and openSUSE. For these both distros only a few specific
135 rules are left in their own file, named after the distro. Rules which
136 are optionally installed, because they are only valid for a specific
137 architecture, or rules for subsystems which are not always used are
138 in etc/udev/packages/.
144 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
145 actions by dynamically created rules.
147 SYMLINK=="<value>" matches agains the entries in the list of
148 currently defined symlinks. The links are not created in the
149 filesystem at that point in time, but the values can be matched.
151 RUN{ignore_error}+="<program>" will ignore any exit code from the
152 program and not record as a failed event.
158 Final merge of patches/features from the Ubuntu package.
164 Control characters in filesystem label strings are no longer silenty
165 removed, but hex-encoded, to be able to uniquely identify the device
166 by its symlink in /dev/disk/by-label/.
167 If libvolume_id is used by mount(8), LABEL= will work as expected,
168 if slashes or other characters are used in the label string.
170 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
171 can be specified now. The TEST key accepts an optional mode mask
172 TEST{0100}=="<is executable file>".
174 Scsi_id now supports a mode without expecting scsi-specific sysfs
175 entries to allow the extraction of cciss-device persistent properties.
181 In the future, we may see uuid's which are just simple character
182 strings (see the DDF Raid Specification). For that reason vol_id now
183 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
184 the creation of symlinks, the *_SAFE values ensure, that no control
185 or whitespace characters are used in the filename.
187 Possible users of libvolume_id, please use the volume_id_get_* functions.
188 The public struct will go away in a future release of the library.
194 Removal of useless extras/eventrecorder.sh.
204 The directory multiplexer for dev.d/ and hotplug.d are finally removed
205 from the udev package.
211 Symlinks can have priorities now, the priority is assigned to the device
212 and specified with OPTIONS="link_priority=100". Devices with higher
213 priorities overwrite the symlinks of devices with lower priorities.
214 If the device that currently owns the link, goes away, the symlink
215 will be removed, and recreated, pointing to the next device with the
216 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
217 more reliable, if multiple devices contain the same metadata and overwrite
220 The dasd_id program is removed from the udev tree, and dasdinfo, with the
221 needed rules, are part of the s390-tools now.
223 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
224 we may get the scsi sysfs mess fixed some day, and this will only catch
225 the devices we are looking for.
227 USB serial numbers for storage devices have the target:lun now appended,
228 to make it possibble to distinguish broken multi-lun devices with all
229 the same SCSI identifiers.
231 Note: The extra "run_directory" which searches and executes stuff in
232 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
233 with the next release. Make sure, that you don't use it anymore, or
234 provides your own implementation of that inefficient stuff.
235 We are tired of reports about a "slow udev", because these directories
236 contain stuff, that runs with _every_ event, instead of using rules,
237 that run programs only for the matching events.
247 DRIVER== will match only for devices that actually have a real
248 driver. DRIVERS== must be used, if parent devices should be
249 included in the match.
251 Libvolume_id's "linux_raid" detection needed another fix.
259 Add additional check to volume_id detection of via_raid, cause
260 some company decided to put a matching pattern all over the empty
261 storage area of their music players.
265 Fix path_id for SAS devices.
269 The udev daemon can be started with --debug-trace now, which will
270 execute all events serialized to get a chance to catch a possible
271 action that crashes the box.
273 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
274 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
275 are excluded from the warning. Referencing parent attributes directly
276 may break when something in the kernel driver model changes. Udev will
277 just find the attribute by walking up the parent chain.
279 Udevtrigger now sorts the list of devices depending on the device
280 dependency, so a "usb" device is triggered after the parent "pci"
285 Revert persistent-storage ata-serial '_' '-' replacement.
291 Udevtrigger can now filter the list of devices to be triggered. Matches
292 for subsystems or sysfs attributes can be specified.
294 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
295 zero-sized files to avoid pointing to /sys and confuse broken tools which
296 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
299 The rules and scripts to create udev rules for persistent network
300 devices and optical drives are in the extras/rules_generator directory
301 now. If you use something similar, please consider replacing your own
302 version with this, to share the support effort. The rule_generator
303 installs its own rules into /etc/udev/rules.d.
305 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
306 the rule_generator depends on cdrom_id to be called in an earlier rule.
312 Renaming of some key names (the old names still work):
313 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
314 (The behavior of the key DRIVER will change soon in one of the next
315 releases, to match only the event device, please switch to DRIVERS
316 instead. If DRIVER is used, it will behave like DRIVERS, but an error
318 With the new key names, we have a more consistent and simpler scheme.
319 We can match the properties of the event device only, with: KERNEL,
320 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
321 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
322 longer mentioned in the man page and should be switched in the rule
325 ATTR{file}="value" can be used now, to write to a sysfs file of the
326 event device. Instead of:
327 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
329 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
331 All the PHYSDEV* keys are deprecated and will be removed from a
333 PHYDEVPATH - is the path of a parent device and should not be
335 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
336 matched with SUBSYSTEMS==
337 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
338 Newer kernels will have DRIVER in the environment,
339 for older kernels udev puts in. Class device will
340 no longer carry this property of a parent and
341 DRIVERS== can be used to match such a parent value.
342 Note that ENV{DRIVER} is only available for a few bus devices, where
343 the driver is already bound at device event time. On coldplug, the
344 events for a lot devices are already bound to a driver, and they will have
345 that value set. But on hotplug, at the time the kernel creates the device,
346 it can't know what driver may claim the device after that, therefore
347 in most cases it will be empty.
349 Failed events should now be re-triggered with:
350 udevtrigger --retry-failed.
351 Please switch to this command, so we keep the details of the /dev/.udev/failed/
352 files private to the udev tools. We may need to switch the current symlink
353 target, cause some obviously broken tools try to scan all files in /dev
354 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
355 million times. This takes ages on slow boxes.
357 The udevinfo attribute walk (-a) now works with giving a device node
358 name (-n) instead of a devpath (-p). The query now always works, also when
359 no database file was created by udev.
361 The built-in /etc/passwd /etc/group parser is removed, we always depend on
362 getpwnam() and getgrnam() now. One of the next releases will depend on
363 fnmatch() and may use getopt_long().
367 Bugfixes and small improvements.
371 Fix path_id for recent kernels.
377 Added support for swapping network interface names, by temporarily
378 renaming the device and wait for the target name to become free.
382 The built-in MODALIAS key and substitution is removed.
386 The binary firmware helper is replaced by the usual simple
387 shell script. Udevsend is removed from the tree.
395 Some more keys require the correct use of '==' and '=' depending
396 on the kind of operation beeing an assignment or a match. Rules
397 with invalid operations are skipped and logged to syslog. Please
398 test with udevtest if the parsing of your rules throws errors and
399 fix possibly broken rules.
403 Provide "udevsettle" to wait for all current udev events to finish.
404 It also watches the current kernel netlink queue by comparing the
405 even sequence number to make sure that there are no current pending
406 events that have not already arrived in the daemon.
410 Fix rule to skip persistent rules for removable IDE devices, which
411 also skipped optical IDE drives.
413 All *_id program are installed in /lib/udev/ by default now.
415 No binary is stripped anymore as this should be done in the
416 packaging process and not at build time.
418 libvolume_id is provided as a shared library now and vol_id is
419 linked against it. Also one of the next HAL versions will require
420 this library, and the HAL build process will also require the
421 header file to be installed. The copy of the same code in HAL will
422 be removed to have only a single copy left on the system.
426 Add persistent links for SCSI tapes. The rules file is renamed
427 to 60-persistent-storage.rules.
429 Create persistent path for usb devices. Can be used for all sorts
430 of devices that can't be distinguished by other properties like
431 multiple identical keyboards and mice connected to the same box.
433 Provide "udevtrigger" program to request events on coldplug. The
434 shell script is much too slow with thousends of devices.
438 Fix persistent disk rules to exclude removable IDE drives.
440 Warn if %e, $modalias or MODALIAS is used.
444 Fix queue export, which wasn't correct for subsequent add/remove
445 events for the same device.
449 Fix cramfs detection on big endian.
451 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
456 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
457 attributes were only checked at the parent device that matched the
458 by BUS requested subsystem. Fix it to also look at the device we
459 received the event for.
461 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
466 Fix a bug where NAME="" would prevent RUN from beeing executed.
468 RUN="/bin/program" does not longer automatically add the subsystem
469 as the first parameter. This is from the days of /sbin/hotplug
470 which is dead now and it's just confusing to need to add a space at
471 the end of the program name to prevent this.
472 If you use rules that need the subsystem as the first parameter,
473 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
474 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
478 The udev man page has moved to udev(7) as it does not describe a command
479 anymore. The programs udev, udevstart and udevsend are no longer installed
480 by default and must be copied manually, if they should be installed or
481 included in a package.
483 Fix a bug where "ignore_device" could run earlier collected RUN keys before
484 the ignore rule was applied.
486 More preparation for future sysfs changes. usb_id and scsi_id no longer
487 depend on a magic order of devices in the /devices chain. Specific devices
488 should be requested by their subsytem.
490 This will always find the scsi parent device without depending on a specific
492 dev = sysfs_device_get(devpath);
493 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
495 The "device" link in the current sysfs layout will be automatically
496 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
497 parent in the devpath. If a device is requested by it's symlink, like all
498 class devices in the new sysfs layout will look like, it gets automatically
499 resolved and substituted with the real devpath and not the symlink path.
502 A similar logic must be applied to _all_ sysfs users, including
503 scripts, that search along parent devices in sysfs. The explicit use of
504 the "device" link must be avoided. With the future sysfs layout all
505 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
506 back to the "class" or the "bus". The layout of the parent devices in
507 /devices is not necessarily expected to be stable across kernel releases and
508 searching for parents by their subsystem should make sysfs users tolerant
509 for changed parent chains.
513 Prepare udev to work with the experimental kernel patch, that moves
514 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
516 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
517 moving the class devices to /sys/devices.
519 Thanks again to Marco for help finding a hopefully nice compromise
520 to make %b simpler and working again.
524 Complete removal of libsysfs, replaced by simple helper functions
525 which are much simpler and a bit faster. The udev daemon operatesentirely
526 on event parameters and does not use sysfs for simple rules anymore.
527 Please report any new bugs/problems, that may be caused by this big
528 change. They will be fixed immediately.
530 The enumeration format character '%e' is deprecated and will be
531 removed sometimes from a future udev version. It never worked correctly
532 outside of udevstart, so we can't use it with the new parallel
533 coldplug. A simple enumeration is as useless as the devfs naming
534 scheme, just get rid of both if you still use it.
536 MODALIAS and $modalias is not needed and will be removed from one of
537 the next udev versions, replace it in all rules with ENV{MODALIAS} or
538 the sysfs "modalias" value.
540 Thanks a lot to Marco for all his help on finding and fixing bugs.
544 Let scsi_id request libata drive serial numbers from page 0x80.
546 Renamed etc/udev/persistent.rules to persistent-disk.rules and
547 added /dev/disk/by-name/* for device mapper device names.
549 Removed %e from the man page. It never worked reliably outside
550 of udevstart and udevstart is no longer recommended to use.
554 Symlinks are now exported to the event environment. Hopefully it's no
555 longer needed to run udevinfo from an event process, like it was
556 mentioned on the hotplug list:
557 UDEV [1134776873.702967] add@/block/sdb
560 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
564 Fix a problem if udevsend is used as the hotplug handler and tries to use
565 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
566 and this kind of problems will hopefully go away soon.
570 All built-in logic to work around bad sysfs timing is removed with this
571 version. The need to wait for sysfs files is almost fixed with a kernel
572 version that doesn't work with this udev version anyway. Until we fix
573 the timing of the "bus" link creation, the former integrated logic should
574 be emulated by a rule placed before all other rules:
575 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
577 The option "udev_db" does no longer exist. All udev state will be in
578 /$udev_root/.udev/ now, there is no longer an option to set this
580 If the init script or something else used this value, just depend on
581 this hardcoded path. But remember _all_content_ of this directory is
582 still private to udev and can change at any time.
584 Default location for rule sripts and helper programs is now: /lib/udev/.
585 Everything that is not useful on the commandline should go into this
586 directory. Some of the helpers in the extras folder are installed there
587 now. The rules need to be changed, to find the helpers there.
589 Also /lib/udev/devices is recommended as a directory where packages or
590 the user can place real device nodes, which get copied over to /dev at
591 every boot. This should replace the various solutions with custom config
594 Udevsend does no longer start the udev daemon. This must be done with
595 the init script that prepares /dev on tmpfs and creates the initial nodes,
596 before starting the daemon.
600 Silent a too verbose error logging for the old hotplug.d/ dev.d/
603 The copy of klibc is removed. A systemwide installed version of klibc
604 should be used to build a klibc udev now.
608 NAME="" will not create any nodes, but execute RUN keys. To completely
609 ignore an event the OPTION "ignore_device" should be used.
611 After removal of the reorder queue, events with a TIMEOUT can be executed
612 without any queuing now.
616 Fixed bug in udevd, if inotify is not available. We depend on netlink
617 uevents now, kernels without that event source will not work with that
618 version of udev anymore.
622 The rule parsing happens now in the daemon once at startup, all udev
623 event processes inherit the already parsed rules from the daemon.
624 It is shipped with SUSE10.0 and reduces heavily the system load at
625 startup. The option to save precompiled rules and let the udev process
626 pick the them up is removed, as it's no longer needed.
628 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
629 device. Libsysfs is changed to "translate" the requested link into the
630 real device path, as it would happen with the hotplug event. Otherwise
631 device removal and the udev database will not work.
633 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
636 A few improvements for vol_id, the filesytem probing code.
640 Fix a stupid typo in extras/run_directory for "make install".
642 scsi_id creates the temporary devnode now in /dev for usage with a
643 non-writable /tmp directory.
645 The uevent kernel socket buffer can carry app. 50.000 events now,
646 let's see who can break this again. :)
648 The upcoming kernel will have a new input driver core integration.
649 Some class devices are now symlinks to the real device. libsysfs
650 needs a fix for this to work correctly. Udevstart of older udev
651 versions will _not_ create these devices!
655 Fix a 'install' target in the Makefile, that prevents EXTRAS from
660 A bunch of mostly trivial bugfixes. From now on no node name or
661 symlink name can contain any character than plain whitelisted ascii
662 characters or validated utf8 byte-streams. This is needed for the
663 /dev/disk/by-label/* links, because we import untrusted data and
664 export it to the filesystem.
668 More bugfixes. If udevd was started from the kernel, we don't
669 have stdin/stdout/stderr, which broke the forked tools in some
674 Bugfix. udevstart event ordering was broken for a long time.
675 The new run_program() uncovered it, because /dev/null was not
676 available while we try to run external programs.
677 Now udevstart should create it before we run anything.
681 Minor bugfixes and some distro rules updates. If you don't have the
682 persistent disk rules in /dev/disk/by-*/* on your distro, just
683 grab it from here. :)
687 We can use socket communication now to pass events from udev to
689 RUN+="socket:/org/freedesktop/hal/udev_event"
690 will pass the whole udev event to the HAL daemon without the need
691 for a forked helper. (See ChangeLog for udevmonitor, as an example)
695 Mostly bugfixes and see ChangeLog.
697 The test for the existence of an environment value should be
699 ENV{KEY}=="*" to ENV{KEY}=="?*"
700 because "*" will not fail anymore, if the key does not exist or
705 Bugfixes and a few tweaks described in the ChangeLog.
709 Mostly a Bugfix release.
711 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
712 timing with custom rules.
716 We changed the internal rule storage format. Our large rule files took
717 2 MB of RAM, with the change we are down to 99kB.
719 If the device-node has been created with default name and no symlink or
720 options are to remenber, it is not longer stored in the udevdb. HAL will
721 need to be updated to work correctly with that change.
723 To overrride optimization flags, OPTFLAGS may be used now.
731 Major changes happened with this release. The goal is to take over the
732 complete kernel-event handling and provide a more efficient way to dispatch
733 kernel events. Replacing most of the current shell script logic and the
734 kernel forked helper with a netlink-daemon and a rule-based event handling.
736 o udevd listens to netlink events now. The first valid netlink event
737 will make udevd ignore any message from udevsend that contains a
738 SEQNUM, to avoid duplicate events. The forked events can be disabled
740 echo "" > /proc/sys/kernel/hotplug
741 For full support, the broken input-subsytem needs to be fixed, not to
742 bypass the driver core.
744 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
745 removed from udev itself and must be emulated by calling small
746 helper binaries provided in the extras folder:
747 make EXTRAS=extras/run_directory/
748 will build udev_run_devd and udev_run_hotplugd, which can be called
749 from a rule if needed:
750 RUN+="/sbin/udev_run_hotplugd"
751 The recommended way to handle this is to convert all the calls from
752 the directories to explicit udev rules and get completely rid of the
753 multiplexing. (To catch a ttyUSB event, you now no longer need to
754 fork and exit 300 tty script instances you are not interested in, it
755 is just one rule that matches exactly the device.)
757 o udev handles now _all_ events not just events for class and block
758 devices, this way it is possible to control the complete event
759 behavior with udev rules. Especially useful for rules like:
760 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
762 o As used in the modalias rule, udev supports now textual
763 substitution placeholder along with the usual format chars. This
764 needs to be documented, for now it's only visible in udev_rules_parse.c.
766 o The rule keys support now more operations. This is documented in the
767 man page. It is possible to add values to list-keys like the SYMLINK
768 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
769 Also "final"-assignments are supported by using KEY:="value", which will
770 prevent changing the key by any later rule.
772 o kernel 2.6.12 has the "detached_state" attribute removed from
773 sysfs, which was used to recognize sysfs population. We switched that
774 to wait for the "bus" link, which is only available in kernels after 2.6.11.
775 Running this udev version on older kernels may cause a short delay for
778 o To provide infrastructure for persistent device naming, the id programs:
779 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
780 to export the probed data in environment key format:
781 pim:~ # /sbin/ata_id --export /dev/hda
782 ID_MODEL=HTS726060M9AT00
783 ID_SERIAL=MRH401M4G6UM9B
787 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
788 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
791 kay@pim:~> tree /dev/disk
794 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
795 | `-- IBM-Memory_Key -> ../../sda
797 | |-- swap -> ../../hda1
798 | |-- date -> ../../sda1
799 | `-- home -> ../../hda3
801 |-- 2E08712B0870F2E7 -> ../../hda3
802 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
803 |-- E845-7A89 -> ../../sda1
804 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
806 The IMPORT= operation will import these keys in the environment and make
807 it available for later PROGRAM= and RUN= executed programs. The keys are
808 also stored in the udevdb and can be queried from there with one of the
811 o A few binaries are silently added to the repository, which can be used
812 to replay kernel events from initramfs instead of using coldplug. udevd
813 can be instructed now to queue-up events while the stored events from
814 initramfs are filled into the udevd-queue. This code is still under
815 development and there is no documentation now besides the code itself.
816 The additional binaries get compiled, but are not installed by default.
818 o There is also a temporary fix for a performance problem where too many
819 events happen in parallel and every event needs to parse the rules.
820 udev can now read precompiled rules stored on disk. This is likely to be
821 replaced by a more elegant solution in a future udev version.
825 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
826 Fix for libsysfs not to expect this file was added.
830 All rules are applied now, but only the first matching rule with a NAME-key
831 will be applied. All later rules with NAME-key are completely ignored. This
832 way system supplied symlinks or permissions gets applied to user-defined
836 Please check your rules setup, if you may need to add OPTIONS="last_rule"
837 to some rules, to keep the old behavior.
839 The rules are read on "remove"-events too. That makes is possible to match
840 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
841 instruct udev to ignore an event (OPTIONS="ignore_device").
842 The new ACTION-key may be used to let a rule act only at a "remove"-event.
844 The new RUN-key supports rule-based execution of programs after device-node
845 handling. This is meant as a general replacement for the dev.d/-directories
846 to give fine grained control over the execution of programs.
848 The %s{}-sysfs format char replacement values are searched at any of the
849 devices in the device chain now, not only at the class-device.
851 We support log priority levels now. The value udev_log in udev.conf is used
852 to determine what is printed to syslog. This makes it possible to
853 run a version with compiled-in debug messages in a production environment
854 which is sometimes needed to find a bug.
855 It is still possible to supress the inclusion of _any_ syslog usage with
856 USE_LOG=false to create the smallest possible binaries if needed.
857 The configured udev_log value can be overridden with the environment variable
862 Possible use of a system-wide klibc:
863 make USE_KLIBC=true KLCC=/usr/bin/klcc all
864 will link against an external klibc and our own version will be ignored.
868 We support an unlimited count of symlinks now.
870 If USE_STATIC=true is passed to a glibc build, we link statically and use
871 a built-in userdb parser to resolve user and group names.
873 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
874 we walk up the chain of physical devices to find a match.
876 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
877 easy to skip certain attribute matches without composing rules with weird
878 character class negations like:
879 KERNEL="[!s][!c][!d]*"
880 this can now be replaced with:
882 The current simple '=' is still supported, and should work as it does today,
883 but existing rules should be converted if possible, to be better readable.
885 We have new ENV{}== key now, to match against a maximum of 5 environment
888 udevstart is its own binary again, because we don't need co carry this araound
889 with every forked event.
~ianmdlvl / elogind.git / blob