systemd 221 发布，此版本更新内容如下： * The sd-bus.h and sd-event.h APIs have now been declared stable and have been added to the official interface of libsystemd.so. * kdbus support is no longer compile-time optional. * The minimal required util-linux version has been bumped to 2.26. * Support for chkconfig (--enable-chkconfig) was removed in favor of calling an abstraction tool /lib/systemd/systemd-sysv-install. * If there's a systemd unit and a SysV init script for the same service name, and the user executes "systemctl enable" for it (or a related call), then this will now enable both (or execute the related operation on both), not just the unit. * The libudev API documentation has been converted from gtkdoc into man pages. * gudev has been removed from the systemd tree, it is now an external project. * The systemd-cgtop tool learnt a new --raw switch to generate "raw" (machine parsable) output. * networkd's IPForwarding= .network file setting learnt the new setting "kernel" * The systemd-logind bus API now exposes a new boolean property "Docked" 详细改进请看更新日志，下载：systemd-221.tar.xz。 systemd是一个init程序。根据之前 Upstart的一些介绍大家应该简要了解了传统Sysvinit系统的不足之处。不过，这次的systemd的设计思想更为超前，也可以说是借鉴了OSX上launchd的思路。 systemd 221 发布，Linux 的 init 程序下载地址
