mirror of
https://github.com/systemd/systemd.git
synced 2026-08-09 09:32:04 +00:00
f8b69d1dfc
The behaviour of the common name##_from_string conversion is surprising. It accepts not only the strings from name##_table but also any number that falls within the range of the table. The order of items in most of our tables is an internal affair. It should not be visible to the user. I know of a case where the surprising numeric conversion leads to a crash. We will allow the direct numeric conversion only for the tables where the mapping of strings to numeric values has an external meaning. This holds for the following lookup tables: - netlink_family, ioprio_class, ip_tos, sched_policy - their numeric values are stable as they are defined by the Linux kernel interface. - log_level, log_facility_unshifted - the well-known syslog interface. We allow the user to use numeric values whose string names systemd does not know. For instance, the user may want to test a new kernel featuring a scheduling policy that did not exist when his systemd version was released. A slightly unpleasant effect of this is that the name##_to_string conversion cannot return pointers to constant strings anymore. The strings have to be allocated on demand and freed by the caller.
systemd System and Service Manager
DETAILS:
http://0pointer.de/blog/projects/systemd.html
WEB SITE:
http://www.freedesktop.org/wiki/Software/systemd
GIT:
git://anongit.freedesktop.org/systemd/systemd
ssh://git.freedesktop.org/git/systemd/systemd
GITWEB:
http://cgit.freedesktop.org/systemd/systemd
MAILING LIST:
http://lists.freedesktop.org/mailman/listinfo/systemd-devel
http://lists.freedesktop.org/mailman/listinfo/systemd-commits
IRC:
#systemd on irc.freenode.org
BUG REPORTS:
https://bugs.freedesktop.org/enter_bug.cgi?product=systemd
AUTHOR:
Lennart Poettering
Kay Sievers
...and many others
LICENSE:
LGPLv2.1+ for all code
- except sd-daemon.[ch] and sd-readahead.[ch] which are MIT
- except src/udev/ which is GPLv2.0+
REQUIREMENTS:
Linux kernel >= 2.6.39
with devtmpfs
with cgroups (but it's OK to disable all controllers)
optional but strongly recommended: autofs4, ipv6
dbus >= 1.4.0
libcap
libblkid >= 2.20 (from util-linux)
libkmod >= 5
PAM >= 1.1.2 (optional)
libcryptsetup (optional)
libgcrypt (optional)
libaudit (optional)
libacl (optional)
libattr (optional)
libselinux (optional)
liblzma (optional)
tcpwrappers (optional)
libgcrypt (optional)
libqrencode (optional)
libmicrohttpd (optional)
When you build from git you need the following additional dependencies:
docbook-xsl
xsltproc
automake
autoconf
libtool
intltool
gperf
gtkdocize (optional)
python (optional)
make, gcc, and similar tools
During runtime you need the following dependencies:
util-linux > v2.18 (requires fsck -l, agetty -s)
sulogin (from sysvinit-tools, optional but recommended)
dracut (optional)
When systemd-hostnamed is used it is strongly recommended to
install nss-myhostname to ensure that in a world of
dynamically changing hostnames the hostname stays resolveable
under all circumstances. In fact, systemd-hostnamed will warn
if nss-myhostname is not installed. Packagers are encouraged to
add a dependency on nss-myhostname to the package that
includes systemd-hostnamed.
Note that D-Bus can link against libsystemd-login.so, which
results in a cyclic build dependency. To accommodate for this
please build D-Bus without systemd first, then build systemd,
then rebuild D-Bus with systemd support.
WARNINGS:
systemd will warn you during boot if /etc/mtab is not a
symlink to /proc/mounts. Please ensure that /etc/mtab is a
proper symlink.
systemd will warn you during boot if /usr is on a different
file system than /. While in systemd itself very little will
break if /usr is on a separate partition many of its
dependencies very likely will break sooner or later in one
form or another. For example udev rules tend to refer to
binaries in /usr, binaries that link to libraries in /usr or
binaries that refer to data files in /usr. Since these
breakages are not always directly visible systemd will warn
about this, since this kind of file system setup is not really
supported anymore by the basic set of Linux OS components.
For more information on this issue consult
http://freedesktop.org/wiki/Software/systemd/separate-usr-is-broken
To run systemd under valgrind, compile with VALGRIND defined
(e.g. ./configure CPPFLAGS='... -DVALGRIND=1'). Otherwise,
false positives will be triggered by code which violates
some rules but is actually safe.
ENGINEERING AND CONSULTING SERVICES:
ProFUSION <http://profusion.mobi> offers professional
engineering and consulting services for systemd for embedded
and other use. Please contact Gustavo Barbieri
<barbieri@profusion.mobi> for more information.
Disclaimer: This notice is not a recommendation or official
endorsement. However, ProFUSION's upstream work has been very
beneficial for the systemd project.