[ANNOUNCE] systemd v237
(too old to reply)
Lennart Poettering
2018-01-28 16:08:51 UTC

I am happy to announce that we just tagged systemd v237:



* Some keyboards come with a zoom see-saw or rocker which until now got
mapped to the Linux "zoomin/out" keys in hwdb. However, these
keycodes are not recognized by any major desktop. They now produce
Up/Down key events so that they can be used for scrolling.

* INCOMPATIBILITY: systemd-tmpfiles' "f" lines changed behaviour
slightly: previously, if an argument was specified for lines of this
type (i.e. the right-most column was set) this string was appended to
existing files each time systemd-tmpfiles was run. This behaviour was
different from what the documentation said, and not particularly
useful, as repeated systemd-tmpfiles invocations would not be
idempotent and grow such files without bounds. With this release
behaviour has been altered slightly, to match what the documentation
says: lines of this type only have an effect if the indicated files
don't exist yet, and only then the argument string is written to the

* FUTURE INCOMPATIBILITY: In systemd v238 we intend to slightly change
systemd-tmpfiles behaviour: previously, read-only files owned by root
were always excluded from the file "aging" algorithm (i.e. the
automatic clean-up of directories like /tmp based on
atime/mtime/ctime). We intend to drop this restriction, and age files
by default even when owned by root and read-only. This behaviour was
inherited from older tools, but there have been requests to remove
it, and it's not obvious why this restriction was made in the first
place. Please speak up now, if you are aware of software that reqires
this behaviour, otherwise we'll remove the restriction in v238.

* A new environment variable $SYSTEMD_OFFLINE is now understood by
systemctl. It takes a boolean argument. If on, systemctl assumes it
operates on an "offline" OS tree, and will not attempt to talk to the
service manager. Previously, this mode was implicitly enabled if a
chroot() environment was detected, and this new environment variable
now provides explicit control.

* .path and .socket units may now be created transiently, too.
Previously only service, mount, automount and timer units were
supported as transient units. The systemd-run tool has been updated
to expose this new functionality, you may hence use it now to bind
arbitrary commands to path or socket activation on-the-fly from the
command line. Moreover, almost all properties are now exposed for the
unit types that already supported transient operation.

* The systemd-mount command gained support for a new --owner= parameter
which takes a user name, which is then resolved and included in uid=
and gid= mount options string of the file system to mount.

* A new unit condition ConditionControlGroupController= has been added
that checks whether a specific cgroup controller is available.

* Unit files, udev's .link files, and systemd-networkd's .netdev and
.network files all gained support for a new condition
ConditionKernelVersion= for checking against specific kernel

* In systemd-networkd, the [IPVLAN] section in .netdev files gained
support for configuring device flags in the Flags= setting. In the
same files, the [Tunnel] section gained support for configuring
AllowLocalRemote=. The [Route] section in .network files gained
support for configuring InitialCongestionWindow=,
InitialAdvertisedReceiveWindow= and QuickAck=. The [DHCP] section now
understands RapidCommit=.

* systemd-networkd's DHCPv6 support gained support for Prefix

* sd-bus gained support for a new "watch-bind" feature. When this
feature is enabled, an sd_bus connection may be set up to connect to
an AF_UNIX socket in the file system as soon as it is created. This
functionality is useful for writing early-boot services that
automatically connect to the system bus as soon as it is started,
without ugly time-based polling. systemd-networkd and
systemd-resolved have been updated to make use of this
functionality. busctl exposes this functionality in a new
--watch-bind= command line switch.

* sd-bus will now optionally synthesize a local "Connected" signal as
soon as a D-Bus connection is set up fully. This message mirrors the
already existing "Disconnected" signal which is synthesized when the
connection is terminated. This signal is generally useful but
particularly handy in combination with the "watch-bind" feature
described above. Synthesizing of this message has to be requested
explicitly through the new API call sd_bus_set_connected_signal(). In
addition a new call sd_bus_is_ready() has been added that checks
whether a connection is fully set up (i.e. between the "Connected" and
"Disconnected" signals).

* sd-bus gained two new calls sd_bus_request_name_async() and
sd_bus_release_name_async() for asynchronously registering bus
names. Similar, there is now sd_bus_add_match_async() for installing
a signal match asynchronously. All of systemd's own services have
been updated to make use of these calls. Doing these operations
asynchronously has two benefits: it reduces the risk of deadlocks in
case of cyclic dependencies between bus services, and it speeds up
service initialization since synchronization points for bus
round-trips are removed.

* sd-bus gained two new calls sd_bus_match_signal() and
sd_bus_match_signal_async(), which are similar to sd_bus_add_match()
and sd_bus_add_match_async() but instead of taking a D-Bus match
string take match fields as normal function parameters.

* sd-bus gained two new calls sd_bus_set_sender() and
sd_bus_message_set_sender() for setting the sender name of outgoing
messages (either for all outgoing messages or for just one specific
one). These calls are only useful in direct connections as on
brokered connections the broker fills in the sender anyway,
overwriting whatever the client filled in.

* sd-event gained a new pseudo-handle that may be specified on all API
calls where an "sd_event*" object is expected: SD_EVENT_DEFAULT. When
used this refers to the default event loop object of the calling
thread. Note however that this does not implicitly allocate one —
which has to be done prior by using sd_event_default(). Similarly
sd-bus gained three new pseudo-handles SD_BUS_DEFAULT,
SD_BUS_DEFAULT_USER, SD_BUS_DEFAULT_SYSTEM that may be used to refer
to the default bus of the specified type of the calling thread. Here
too this does not implicitly allocate bus connection objects, this
has to be done prior with sd_bus_default() and friends.

* sd-event gained a new call pair
sd_event_source_{get|set}_io_fd_own(). This may be used to request
automatic closure of the file descriptor an IO event source watches
when the event source is destroyed.

* systemd-networkd gained support for natively configuring WireGuard

* In previous versions systemd synthesized user records both for the
"nobody" (UID 65534) and "root" (UID 0) users in nss-systemd and
internally. In order to simplify distribution-wide renames of the
"nobody" user (like it is planned in Fedora: nfsnobody → nobody), a
new transitional flag file has been added: if
/etc/systemd/dont-synthesize-nobody exists synthesizing of the 65534
user and group record within the systemd codebase is disabled.

* systemd-notify gained a new --uid= option for selecting the source
user/UID to use for notification messages sent to the service

* journalctl gained a new --grep= option to list only entries in which
the message matches a certain pattern. By default matching is case
insensitive if the pattern is lowercase, and case sensitive
otherwise. Option --case-sensitive=yes|no can be used to override
this an specify case sensitivity or case insensitivity.

* There's now a "systemd-analyze service-watchdogs" command for printing
the current state of the service runtime watchdog, and optionally
enabling or disabling the per-service watchdogs system-wide if given a
boolean argument (i.e. the concept you configure in WatchdogSec=), for
debugging purposes. There's also a kernel command line option
systemd.service_watchdogs= for controlling the same.

* Two new "log-level" and "log-target" options for systemd-analyze were
addded that merge the now deprecated get-log-level, set-log-level and
get-log-target, set-log-target pairs. The deprecated options are still
understood for backwards compatibility. The two new options print the
current value when no arguments are given, and set them when a
level/target is given as an argument.

* sysusers.d's "u" lines now optionally accept both a UID and a GID
specification, separated by a ":" character, in order to create users
where UID and GID do not match.

Contributions from: Adam Duskett, Alan Jenkins, Alexander Kuleshov,
Alexis Deruelle, Andrew Jeddeloh, Armin Widegreen, Batuhan Osman
Taşkaya, Björn Esser, bleep_blop, Bruce A. Johnson, Chris Down, Clinton
Roy, Colin Walters, Daniel Rusek, Dimitri John Ledkov, Dmitry Rozhkov,
Evgeny Vereshchagin, Ewout van Mansom, Felipe Sateler, Franck Bui,
Frantisek Sumsal, George Gaydarov, Gianluca Boiano, Hans-Christian
Noren Egtvedt, Hans de Goede, Henrik Grindal Bakken, Jan Alexander
Steffens, Jan Klötzke, Jason A. Donenfeld, jdkbx, Jérémy Rosen,
Jerónimo Borque, John Lin, John Paul Herold, Jonathan Rudenberg, Jörg
Thalheim, Ken (Bitsko) MacLeod, Larry Bernstone, Lennart Poettering,
Lucas Werkmeister, Maciej S. Szmigiero, Marek Čermák, Martin Pitt,
Mathieu Malaterre, Matthew Thode, Matthias-Christian Ott, Max Harmathy,
Michael Biebl, Michael Vogt, Michal Koutný, Michal Sekletar, Michał
Szczepański, Mike Gilbert, Nathaniel McCallum, Nicolas Chauvet, Olaf
Hering, Olivier Schwander, Patrik Flykt, Paul Cercueil, Peter Hutterer,
Piotr Drąg, Raphael Vogelgsang, Reverend Homer, Robert Kolchmeyer,
Samuel Dionne-Riel, Sergey Ptashnick, Shawn Landden, Susant Sahani,
Sylvain Plantefève, Thomas H. P. Andersen, Thomas Huth, Tomasz
Bachorski, Vladislav Vishnyakov, Wieland Hoffmann, Yu Watanabe, Zachary
Winnerman, Zbigniew Jędrzejewski-Szmek, Дамјан Георгиевски, Дилян

— Brno, 2018-01-28


Lennart Poettering, Red Hat