man: be more explicit about the usefulness of --system

[elogind.git] / man / systemd.xml

diff --git a/man/systemd.xml b/man/systemd.xml
index 428e17f63becc3375bc5bb0d1dc9f192f0dae85a..6aa4f7052706b1f0fd75a0aa2358997312b9cc7b 100644 (file)
--- a/man/systemd.xml
+++ b/man/systemd.xml
@@ -141,14 +141,20 @@
                                 <listitem><para>Tell systemd to run a
                                 system instance (resp. session
                                 instance), even if the process ID is
-                                not 1 (resp. is 1), i.e. systemd is not
-                                (resp. is) run as init process.
+                                not 1 (resp. is 1), i.e. systemd is
+                                not (resp. is) run as init process.
                                 Normally it should not be necessary to
                                 pass these options, as systemd
                                 automatically detects the mode it is
                                 started in. These options are hence of
-                                little use except for
-                                debugging.</para></listitem>
+                                little use except for debugging. Note
+                                that it is not supported booting and
+                                maintaining a full system with systemd
+                                running in <option>--system</option>
+                                mode, but PID not 1. In practice,
+                                passing <option>--system</option> explicitly is
+                                only useful in conjunction with
+                                <option>--test</option>.</para></listitem>
                         </varlistentry>
                         <varlistentry>
                                 <term><option>--dump-core</option></term>
@@ -440,6 +446,11 @@
                 ideas behind systemd please refer to the <ulink
                 url="http://0pointer.de/blog/projects/systemd.html">Original
                 Design Document</ulink>.</para>
+
+                <para>Note that some but not all interfaces provided
+                by systemd are covered by the <ulink
+                url="http://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise">Interface
+                Stability Promise</ulink>.</para>
         </refsect1>
 
         <refsect1>