We use that on all other services, and hence should here too. Otherwise
the service will be killed with SIGSYS when doing something not
whitelisted, which is a bit crass.
When a DHCP server provides only a gateway, the networkd-dhcp4 code adds a
default route using that gateway, and sets the just-provided address as
the route's prefsrc; this was added in commit
46b0c76e2c
However, if the DHCP server has also provided classless route(s), these
are used instead of a default route using the provided gateway; the
networkd-dhcp4 code sets up the classless routes, but does not use the
just-provided dhcp address as the prefsrc of the route(s). Note that
it also doesn't set the prefsrc for static routes, though it should.
If the interface has only the dhcp-provided address, this is not usually
a problem, but if it has another address (e.g. a static address), then
traffic sent through the dhcp-provided gateway might not use the
dhcp-provided source address. If the gateway router only will route
traffic from the dhcp-provided address, then the dhcp client system's
networking through the router will not work.
Fixes: #12969
$ systemd-analyze dump | head -3
Timestamp firmware: (null)
Timestamp loader: (null)
Timestamp kernel: Mon 2019-07-01 17:21:02 CEST
Since this is a debugging interface, it is OK to change the output format.
The user can infer what "Timestamp firmware: 123.456ms" means.
It was only used for exactly one thing: to substitute in the text in
/var/log/README. But it's use there was completely wrong, because the text
talks about "missing" log files from syslog, so even if we configured systemd
to log to a different directory, the "missing" log files would still be
"missing" from the old location.
Not everybody has those dirs in the filesystem (and they don't need to).
When creating an installation package using $DESTDIR, it is easy enough to
remove or ignore those directories, but if installing into a real root, it
is ugly to create and remove them. Let's add an option so people can skip
it if they want.
Inspired by #12930.
This call can be useful even if a server object is declared.
(Originally this was not supported, because a server typically needs to
handle multiple connections, and thus a synchronous wait on one would
starve the others out. But in some cases it might make sense to have
varlink point-to-point connections — i.e. where the server only handles
a single connection ever — and there it makes sense to synchronously
wait on the one connection).
