5 Tape drive id-data is queried from /dev/bsg/* instead of the tape
6 nodes. This avoids rewinding tapes on open().
12 The symlinks udevcontrol and udevtrigger are no longer installed by
15 The scsi_id program does not depend on sysfs anymore. It can speak
16 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
17 data, which should solve some old problems with tape devices, where
18 we better do not open all tape device nodes to identify the device.
24 The cdrom_id program is replaced by an advanced version, which can
25 detect most common device types, and also properties of the inserted
26 media. This is part of moving some basic functionality from HAL into
27 udev (and the kernel).
33 The last WAIT_FOR_SYSFS rule is removed from the default rules.
35 The symlinks to udevadm for the debugging tools: udevmonitor and
36 udevtest are no longer created.
38 The symlinks to the udevadm man page for the old tool names are
41 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
42 should be prefixed with '@' to indicate that the path is not a
53 Udevstart is removed from the tree, it did not get installed for
54 a long time now, and is long replaced by trigger and settle.
60 All udev tools are merged into a single binary called udevadm.
61 The old names of the tools are built-in commands in udevadm now.
62 Symlinks to udevadm, with the names of the old tools, provide
63 the same functionality as the standalone tools. There is also
64 only a single udevadm.8 man page left for all tools.
66 Tools like mkinitramfs should be checked, if they need to include
67 udevadm in the list of files.
77 The etc/udev/rules.d/ directory now contains a default set of basic
78 udev rules. This initial version is the result of a rules file merge
79 of Fedora and openSUSE. For these both distros only a few specific
80 rules are left in their own file, named after the distro. Rules which
81 are optionally installed, because they are only valid for a specific
82 architecture, or rules for subsystems which are not always used are
83 in etc/udev/packages/.
89 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
90 actions by dynamically created rules.
92 SYMLINK=="<value>" matches agains the entries in the list of
93 currently defined symlinks. The links are not created in the
94 filesystem at that point in time, but the values can be matched.
96 RUN{ignore_error}+="<program>" will ignore any exit code from the
97 program and not record as a failed event.
103 Final merge of patches/features from the Ubuntu package.
109 Control characters in filesystem label strings are no longer silenty
110 removed, but hex-encoded, to be able to uniquely identify the device
111 by its symlink in /dev/disk/by-label/.
112 If libvolume_id is used by mount(8), LABEL= will work as expected,
113 if slashes or other characters are used in the label string.
115 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
116 can be specified now. The TEST key accepts an optional mode mask
117 TEST{0100}=="<is executable file>".
119 Scsi_id now supports a mode without expecting scsi-specific sysfs
120 entries to allow the extraction of cciss-device persistent properties.
126 In the future, we may see uuid's which are just simple character
127 strings (see the DDF Raid Specification). For that reason vol_id now
128 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
129 the creation of symlinks, the *_SAFE values ensure, that no control
130 or whitespace characters are used in the filename.
132 Possible users of libvolume_id, please use the volume_id_get_* functions.
133 The public struct will go away in a future release of the library.
139 Removal of useless extras/eventrecorder.sh.
149 The directory multiplexer for dev.d/ and hotplug.d are finally removed
150 from the udev package.
156 Symlinks can have priorities now, the priority is assigned to the device
157 and specified with OPTIONS="link_priority=100". Devices with higher
158 priorities overwrite the symlinks of devices with lower priorities.
159 If the device that currently owns the link, goes away, the symlink
160 will be removed, and recreated, pointing to the next device with the
161 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
162 more reliable, if multiple devices contain the same metadata and overwrite
165 The dasd_id program is removed from the udev tree, and dasdinfo, with the
166 needed rules, are part of the s390-tools now.
168 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
169 we may get the scsi sysfs mess fixed some day, and this will only catch
170 the devices we are looking for.
172 USB serial numbers for storage devices have the target:lun now appended,
173 to make it possibble to distinguish broken multi-lun devices with all
174 the same SCSI identifiers.
176 Note: The extra "run_directory" which searches and executes stuff in
177 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
178 with the next release. Make sure, that you don't use it anymore, or
179 provides your own implementation of that inefficient stuff.
180 We are tired of reports about a "slow udev", because these directories
181 contain stuff, that runs with _every_ event, instead of using rules,
182 that run programs only for the matching events.
192 DRIVER== will match only for devices that actually have a real
193 driver. DRIVERS== must be used, if parent devices should be
194 included in the match.
196 Libvolume_id's "linux_raid" detection needed another fix.
204 Add additional check to volume_id detection of via_raid, cause
205 some company decided to put a matching pattern all over the empty
206 storage area of their music players.
210 Fix path_id for SAS devices.
214 The udev daemon can be started with --debug-trace now, which will
215 execute all events serialized to get a chance to catch a possible
216 action that crashes the box.
218 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
219 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
220 are excluded from the warning. Referencing parent attributes directly
221 may break when something in the kernel driver model changes. Udev will
222 just find the attribute by walking up the parent chain.
224 Udevtrigger now sorts the list of devices depending on the device
225 dependency, so a "usb" device is triggered after the parent "pci"
230 Revert persistent-storage ata-serial '_' '-' replacement.
236 Udevtrigger can now filter the list of devices to be triggered. Matches
237 for subsystems or sysfs attributes can be specified.
239 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
240 zero-sized files to avoid pointing to /sys and confuse broken tools which
241 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
244 The rules and scripts to create udev rules for persistent network
245 devices and optical drives are in the extras/rules_generator directory
246 now. If you use something similar, please consider replacing your own
247 version with this, to share the support effort. The rule_generator
248 installs its own rules into /etc/udev/rules.d.
250 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
251 the rule_generator depends on cdrom_id to be called in an earlier rule.
257 Renaming of some key names (the old names still work):
258 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
259 (The behavior of the key DRIVER will change soon in one of the next
260 releases, to match only the event device, please switch to DRIVERS
261 instead. If DRIVER is used, it will behave like DRIVERS, but an error
263 With the new key names, we have a more consistent and simpler scheme.
264 We can match the properties of the event device only, with: KERNEL,
265 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
266 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
267 longer mentioned in the man page and should be switched in the rule
270 ATTR{file}="value" can be used now, to write to a sysfs file of the
271 event device. Instead of:
272 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
274 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
276 All the PHYSDEV* keys are deprecated and will be removed from a
278 PHYDEVPATH - is the path of a parent device and should not be
280 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
281 matched with SUBSYSTEMS==
282 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
283 Newer kernels will have DRIVER in the environment,
284 for older kernels udev puts in. Class device will
285 no longer carry this property of a parent and
286 DRIVERS== can be used to match such a parent value.
287 Note that ENV{DRIVER} is only available for a few bus devices, where
288 the driver is already bound at device event time. On coldplug, the
289 events for a lot devices are already bound to a driver, and they will have
290 that value set. But on hotplug, at the time the kernel creates the device,
291 it can't know what driver may claim the device after that, therefore
292 in most cases it will be empty.
294 Failed events should now be re-triggered with:
295 udevtrigger --retry-failed.
296 Please switch to this command, so we keep the details of the /dev/.udev/failed/
297 files private to the udev tools. We may need to switch the current symlink
298 target, cause some obviously broken tools try to scan all files in /dev
299 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
300 million times. This takes ages on slow boxes.
302 The udevinfo attribute walk (-a) now works with giving a device node
303 name (-n) instead of a devpath (-p). The query now always works, also when
304 no database file was created by udev.
306 The built-in /etc/passwd /etc/group parser is removed, we always depend on
307 getpwnam() and getgrnam() now. One of the next releases will depend on
308 fnmatch() and may use getopt_long().
312 Bugfixes and small improvements.
316 Fix path_id for recent kernels.
322 Added support for swapping network interface names, by temporarily
323 renaming the device and wait for the target name to become free.
327 The built-in MODALIAS key and substitution is removed.
331 The binary firmware helper is replaced by the usual simple
332 shell script. Udevsend is removed from the tree.
340 Some more keys require the correct use of '==' and '=' depending
341 on the kind of operation beeing an assignment or a match. Rules
342 with invalid operations are skipped and logged to syslog. Please
343 test with udevtest if the parsing of your rules throws errors and
344 fix possibly broken rules.
348 Provide "udevsettle" to wait for all current udev events to finish.
349 It also watches the current kernel netlink queue by comparing the
350 even sequence number to make sure that there are no current pending
351 events that have not already arrived in the daemon.
355 Fix rule to skip persistent rules for removable IDE devices, which
356 also skipped optical IDE drives.
358 All *_id program are installed in /lib/udev/ by default now.
360 No binary is stripped anymore as this should be done in the
361 packaging process and not at build time.
363 libvolume_id is provided as a shared library now and vol_id is
364 linked against it. Also one of the next HAL versions will require
365 this library, and the HAL build process will also require the
366 header file to be installed. The copy of the same code in HAL will
367 be removed to have only a single copy left on the system.
371 Add persistent links for SCSI tapes. The rules file is renamed
372 to 60-persistent-storage.rules.
374 Create persistent path for usb devices. Can be used for all sorts
375 of devices that can't be distinguished by other properties like
376 multiple identical keyboards and mice connected to the same box.
378 Provide "udevtrigger" program to request events on coldplug. The
379 shell script is much too slow with thousends of devices.
383 Fix persistent disk rules to exclude removable IDE drives.
385 Warn if %e, $modalias or MODALIAS is used.
389 Fix queue export, which wasn't correct for subsequent add/remove
390 events for the same device.
394 Fix cramfs detection on big endian.
396 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
401 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
402 attributes were only checked at the parent device that matched the
403 by BUS requested subsystem. Fix it to also look at the device we
404 received the event for.
406 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
411 Fix a bug where NAME="" would prevent RUN from beeing executed.
413 RUN="/bin/program" does not longer automatically add the subsystem
414 as the first parameter. This is from the days of /sbin/hotplug
415 which is dead now and it's just confusing to need to add a space at
416 the end of the program name to prevent this.
417 If you use rules that need the subsystem as the first parameter,
418 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
419 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
423 The udev man page has moved to udev(7) as it does not describe a command
424 anymore. The programs udev, udevstart and udevsend are no longer installed
425 by default and must be copied manually, if they should be installed or
426 included in a package.
428 Fix a bug where "ignore_device" could run earlier collected RUN keys before
429 the ignore rule was applied.
431 More preparation for future sysfs changes. usb_id and scsi_id no longer
432 depend on a magic order of devices in the /devices chain. Specific devices
433 should be requested by their subsytem.
435 This will always find the scsi parent device without depending on a specific
437 dev = sysfs_device_get(devpath);
438 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
440 The "device" link in the current sysfs layout will be automatically
441 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
442 parent in the devpath. If a device is requested by it's symlink, like all
443 class devices in the new sysfs layout will look like, it gets automatically
444 resolved and substituted with the real devpath and not the symlink path.
447 A similar logic must be applied to _all_ sysfs users, including
448 scripts, that search along parent devices in sysfs. The explicit use of
449 the "device" link must be avoided. With the future sysfs layout all
450 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
451 back to the "class" or the "bus". The layout of the parent devices in
452 /devices is not necessarily expected to be stable across kernel releases and
453 searching for parents by their subsystem should make sysfs users tolerant
454 for changed parent chains.
458 Prepare udev to work with the experimental kernel patch, that moves
459 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
461 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
462 moving the class devices to /sys/devices.
464 Thanks again to Marco for help finding a hopefully nice compromise
465 to make %b simpler and working again.
469 Complete removal of libsysfs, replaced by simple helper functions
470 which are much simpler and a bit faster. The udev daemon operatesentirely
471 on event parameters and does not use sysfs for simple rules anymore.
472 Please report any new bugs/problems, that may be caused by this big
473 change. They will be fixed immediately.
475 The enumeration format character '%e' is deprecated and will be
476 removed sometimes from a future udev version. It never worked correctly
477 outside of udevstart, so we can't use it with the new parallel
478 coldplug. A simple enumeration is as useless as the devfs naming
479 scheme, just get rid of both if you still use it.
481 MODALIAS and $modalias is not needed and will be removed from one of
482 the next udev versions, replace it in all rules with ENV{MODALIAS} or
483 the sysfs "modalias" value.
485 Thanks a lot to Marco for all his help on finding and fixing bugs.
489 Let scsi_id request libata drive serial numbers from page 0x80.
491 Renamed etc/udev/persistent.rules to persistent-disk.rules and
492 added /dev/disk/by-name/* for device mapper device names.
494 Removed %e from the man page. It never worked reliably outside
495 of udevstart and udevstart is no longer recommended to use.
499 Symlinks are now exported to the event environment. Hopefully it's no
500 longer needed to run udevinfo from an event process, like it was
501 mentioned on the hotplug list:
502 UDEV [1134776873.702967] add@/block/sdb
505 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
509 Fix a problem if udevsend is used as the hotplug handler and tries to use
510 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
511 and this kind of problems will hopefully go away soon.
515 All built-in logic to work around bad sysfs timing is removed with this
516 version. The need to wait for sysfs files is almost fixed with a kernel
517 version that doesn't work with this udev version anyway. Until we fix
518 the timing of the "bus" link creation, the former integrated logic should
519 be emulated by a rule placed before all other rules:
520 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
522 The option "udev_db" does no longer exist. All udev state will be in
523 /$udev_root/.udev/ now, there is no longer an option to set this
525 If the init script or something else used this value, just depend on
526 this hardcoded path. But remember _all_content_ of this directory is
527 still private to udev and can change at any time.
529 Default location for rule sripts and helper programs is now: /lib/udev/.
530 Everything that is not useful on the commandline should go into this
531 directory. Some of the helpers in the extras folder are installed there
532 now. The rules need to be changed, to find the helpers there.
534 Also /lib/udev/devices is recommended as a directory where packages or
535 the user can place real device nodes, which get copied over to /dev at
536 every boot. This should replace the various solutions with custom config
539 Udevsend does no longer start the udev daemon. This must be done with
540 the init script that prepares /dev on tmpfs and creates the initial nodes,
541 before starting the daemon.
545 Silent a too verbose error logging for the old hotplug.d/ dev.d/
548 The copy of klibc is removed. A systemwide installed version of klibc
549 should be used to build a klibc udev now.
553 NAME="" will not create any nodes, but execute RUN keys. To completely
554 ignore an event the OPTION "ignore_device" should be used.
556 After removal of the reorder queue, events with a TIMEOUT can be executed
557 without any queuing now.
561 Fixed bug in udevd, if inotify is not available. We depend on netlink
562 uevents now, kernels without that event source will not work with that
563 version of udev anymore.
567 The rule parsing happens now in the daemon once at startup, all udev
568 event processes inherit the already parsed rules from the daemon.
569 It is shipped with SUSE10.0 and reduces heavily the system load at
570 startup. The option to save precompiled rules and let the udev process
571 pick the them up is removed, as it's no longer needed.
573 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
574 device. Libsysfs is changed to "translate" the requested link into the
575 real device path, as it would happen with the hotplug event. Otherwise
576 device removal and the udev database will not work.
578 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
581 A few improvements for vol_id, the filesytem probing code.
585 Fix a stupid typo in extras/run_directory for "make install".
587 scsi_id creates the temporary devnode now in /dev for usage with a
588 non-writable /tmp directory.
590 The uevent kernel socket buffer can carry app. 50.000 events now,
591 let's see who can break this again. :)
593 The upcoming kernel will have a new input driver core integration.
594 Some class devices are now symlinks to the real device. libsysfs
595 needs a fix for this to work correctly. Udevstart of older udev
596 versions will _not_ create these devices!
600 Fix a 'install' target in the Makefile, that prevents EXTRAS from
605 A bunch of mostly trivial bugfixes. From now on no node name or
606 symlink name can contain any character than plain whitelisted ascii
607 characters or validated utf8 byte-streams. This is needed for the
608 /dev/disk/by-label/* links, because we import untrusted data and
609 export it to the filesystem.
613 More bugfixes. If udevd was started from the kernel, we don't
614 have stdin/stdout/stderr, which broke the forked tools in some
619 Bugfix. udevstart event ordering was broken for a long time.
620 The new run_program() uncovered it, because /dev/null was not
621 available while we try to run external programs.
622 Now udevstart should create it before we run anything.
626 Minor bugfixes and some distro rules updates. If you don't have the
627 persistent disk rules in /dev/disk/by-*/* on your distro, just
628 grab it from here. :)
632 We can use socket communication now to pass events from udev to
634 RUN+="socket:/org/freedesktop/hal/udev_event"
635 will pass the whole udev event to the HAL daemon without the need
636 for a forked helper. (See ChangeLog for udevmonitor, as an example)
640 Mostly bugfixes and see ChangeLog.
642 The test for the existence of an environment value should be
644 ENV{KEY}=="*" to ENV{KEY}=="?*"
645 because "*" will not fail anymore, if the key does not exist or
650 Bugfixes and a few tweaks described in the ChangeLog.
654 Mostly a Bugfix release.
656 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
657 timing with custom rules.
661 We changed the internal rule storage format. Our large rule files took
662 2 MB of RAM, with the change we are down to 99kB.
664 If the device-node has been created with default name and no symlink or
665 options are to remenber, it is not longer stored in the udevdb. HAL will
666 need to be updated to work correctly with that change.
668 To overrride optimization flags, OPTFLAGS may be used now.
676 Major changes happened with this release. The goal is to take over the
677 complete kernel-event handling and provide a more efficient way to dispatch
678 kernel events. Replacing most of the current shell script logic and the
679 kernel forked helper with a netlink-daemon and a rule-based event handling.
681 o udevd listens to netlink events now. The first valid netlink event
682 will make udevd ignore any message from udevsend that contains a
683 SEQNUM, to avoid duplicate events. The forked events can be disabled
685 echo "" > /proc/sys/kernel/hotplug
686 For full support, the broken input-subsytem needs to be fixed, not to
687 bypass the driver core.
689 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
690 removed from udev itself and must be emulated by calling small
691 helper binaries provided in the extras folder:
692 make EXTRAS=extras/run_directory/
693 will build udev_run_devd and udev_run_hotplugd, which can be called
694 from a rule if needed:
695 RUN+="/sbin/udev_run_hotplugd"
696 The recommended way to handle this is to convert all the calls from
697 the directories to explicit udev rules and get completely rid of the
698 multiplexing. (To catch a ttyUSB event, you now no longer need to
699 fork and exit 300 tty script instances you are not interested in, it
700 is just one rule that matches exactly the device.)
702 o udev handles now _all_ events not just events for class and block
703 devices, this way it is possible to control the complete event
704 behavior with udev rules. Especially useful for rules like:
705 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
707 o As used in the modalias rule, udev supports now textual
708 substitution placeholder along with the usual format chars. This
709 needs to be documented, for now it's only visible in udev_rules_parse.c.
711 o The rule keys support now more operations. This is documented in the
712 man page. It is possible to add values to list-keys like the SYMLINK
713 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
714 Also "final"-assignments are supported by using KEY:="value", which will
715 prevent changing the key by any later rule.
717 o kernel 2.6.12 has the "detached_state" attribute removed from
718 sysfs, which was used to recognize sysfs population. We switched that
719 to wait for the "bus" link, which is only available in kernels after 2.6.11.
720 Running this udev version on older kernels may cause a short delay for
723 o To provide infrastructure for persistent device naming, the id programs:
724 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
725 to export the probed data in environment key format:
726 pim:~ # /sbin/ata_id --export /dev/hda
727 ID_MODEL=HTS726060M9AT00
728 ID_SERIAL=MRH401M4G6UM9B
732 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
733 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
736 kay@pim:~> tree /dev/disk
739 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
740 | `-- IBM-Memory_Key -> ../../sda
742 | |-- swap -> ../../hda1
743 | |-- date -> ../../sda1
744 | `-- home -> ../../hda3
746 |-- 2E08712B0870F2E7 -> ../../hda3
747 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
748 |-- E845-7A89 -> ../../sda1
749 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
751 The IMPORT= operation will import these keys in the environment and make
752 it available for later PROGRAM= and RUN= executed programs. The keys are
753 also stored in the udevdb and can be queried from there with one of the
756 o A few binaries are silently added to the repository, which can be used
757 to replay kernel events from initramfs instead of using coldplug. udevd
758 can be instructed now to queue-up events while the stored events from
759 initramfs are filled into the udevd-queue. This code is still under
760 development and there is no documentation now besides the code itself.
761 The additional binaries get compiled, but are not installed by default.
763 o There is also a temporary fix for a performance problem where too many
764 events happen in parallel and every event needs to parse the rules.
765 udev can now read precompiled rules stored on disk. This is likely to be
766 replaced by a more elegant solution in a future udev version.
770 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
771 Fix for libsysfs not to expect this file was added.
775 All rules are applied now, but only the first matching rule with a NAME-key
776 will be applied. All later rules with NAME-key are completely ignored. This
777 way system supplied symlinks or permissions gets applied to user-defined
781 Please check your rules setup, if you may need to add OPTIONS="last_rule"
782 to some rules, to keep the old behavior.
784 The rules are read on "remove"-events too. That makes is possible to match
785 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
786 instruct udev to ignore an event (OPTIONS="ignore_device").
787 The new ACTION-key may be used to let a rule act only at a "remove"-event.
789 The new RUN-key supports rule-based execution of programs after device-node
790 handling. This is meant as a general replacement for the dev.d/-directories
791 to give fine grained control over the execution of programs.
793 The %s{}-sysfs format char replacement values are searched at any of the
794 devices in the device chain now, not only at the class-device.
796 We support log priority levels now. The value udev_log in udev.conf is used
797 to determine what is printed to syslog. This makes it possible to
798 run a version with compiled-in debug messages in a production environment
799 which is sometimes needed to find a bug.
800 It is still possible to supress the inclusion of _any_ syslog usage with
801 USE_LOG=false to create the smallest possible binaries if needed.
802 The configured udev_log value can be overridden with the environment variable
807 Possible use of a system-wide klibc:
808 make USE_KLIBC=true KLCC=/usr/bin/klcc all
809 will link against an external klibc and our own version will be ignored.
813 We support an unlimited count of symlinks now.
815 If USE_STATIC=true is passed to a glibc build, we link statically and use
816 a built-in userdb parser to resolve user and group names.
818 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
819 we walk up the chain of physical devices to find a match.
821 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
822 easy to skip certain attribute matches without composing rules with weird
823 character class negations like:
824 KERNEL="[!s][!c][!d]*"
825 this can now be replaced with:
827 The current simple '=' is still supported, and should work as it does today,
828 but existing rules should be converted if possible, to be better readable.
830 We have new ENV{}== key now, to match against a maximum of 5 environment
833 udevstart is its own binary again, because we don't need co carry this araound
834 with every forked event.