The concept is flawed, and mostly useless. Let's finally remove it.
It has been deprecated since 90a2ec10f2 (6
years ago) and we started to warn since
55dadc5c57 (1.5 years ago).
Let's get rid of it altogether.
For users, the square brackets already serve as markup and clearly delineate
the section name from surrounding text. Putting additional markup around that
only adds clutter. Also, we were very inconsistent in using the quotes. Let's
just drop them altogether.
Six years ago we declared it obsolete and removed it from the docs
(c073a0c4a5) and added a note about it in
NEWS. Two years ago we add warning messages about it, indicating the
feature will be removed (41b283d0f1) and
mentioned it in NEWS again.
Let's now kill it for good.
Much like systemd.condition-needs-update= this new switch allows
overriding of a unit file condition, but this time its
ConditionFirstBoot=.
Usecase is also primarily debugging, but could be useful for other
schemes too.
As described in #15603, it is a fairly common setup to use a fqdn as the
configured hostname. But it is often convenient to use just the actual
hostname, i.e. until the first dot. This adds support in tmpfiles, sysusers,
and unit files for %l which expands to that.
Fixes#15603.
The hack with getparent().txt is not very pretty, but the whole
thing seems to work well enough. It is useful to figure out whihc
specifiers are supported where.
We probably can migrate even more, but for now let's just migrate those
which have the 1:1 identical text everywhere.
(Also, let's add the % entry to all specifier tables)
proot provides userspace-powered emulation of chroot and mount --bind,
lending it to be used on environments without unprivileged user
namespaces, or in otherwise restricted environments like Android.
In order to achieve this, proot makes use of the kernel's ptrace()
facility, which we can use in order to detect its presence. Since it
doesn't use any kind of namespacing, including PID namespacing, we don't
need to do any tricks when trying to get the tracer's metadata.
For our purposes, proot is listed as a "container", since we mostly use
this also as the bucket for non-container-but-container-like
technologies like WSL. As such, it seems like a good fit for this
section as well.
