X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsystemd-halt.service.xml;h=0737d058d1533085426d97644b7d1bfb07bf08bc;hp=6957fb984e2faf78643d360449c09114748ddb0d;hb=23a7f0f721ff4e3b3fd4ed87f7d8e01ebad20093;hpb=0127336c01198ef210882207d24257cb3752718b

diff --git a/man/systemd-halt.service.xml b/man/systemd-halt.service.xml
index 6957fb984..0737d058d 100644
--- a/man/systemd-halt.service.xml
+++ b/man/systemd-halt.service.xml
@@ -48,7 +48,7 @@
                 <refname>systemd-reboot.service</refname>
                 <refname>systemd-kexec.service</refname>
                 <refname>systemd-shutdown</refname>
-                <refpurpose>systemd System Shutdown Logic</refpurpose>
+                <refpurpose>System shutdown logic</refpurpose>
         </refnamediv>
 
         <refsynopsisdiv>
@@ -74,25 +74,31 @@
                 <filename>kexec.target</filename> to execute the
                 respective actions.</para>
 
-                <para>When these services are run they ensure that PID
+                <para>When these services are run, they ensure that PID
                 1 is replaced by the
-                <filename>/usr/lib/systemd/system-shutdown</filename>
+                <filename>/usr/lib/systemd/systemd-shutdown</filename>
                 tool which is then responsible for the actual
-                shutdown. Before shutting down this binary will try to
+                shutdown. Before shutting down, this binary will try to
                 unmount all remaining file systems, disable all
                 remaining swap devices, detach all remaining storage
                 devices and kill all remaining processes.</para>
 
+                <para>It is necessary to have this code in a separate binary
+                because otherwise rebooting after an upgrade might be broken —
+                the running PID 1 could still depend on libraries which are not
+                available any more, thus keeping the filesystem busy, which
+                then cannot be re-mounted read-only.</para>
+
                 <para>Immediately before executing the actual system
                 halt/poweroff/reboot/kexec
-                <filename>system-shutdown</filename> will run all
+                <filename>systemd-shutdown</filename> will run all
                 executables in
                 <filename>/usr/lib/systemd/system-shutdown/</filename>
                 and pass one arguments to them: either
-                "<literal>halt</literal>",
-                "<literal>poweroff</literal>",
-                "<literal>reboot</literal>" or
-                "<literal>kexec</literal>", depending on the chosen
+                <literal>halt</literal>,
+                <literal>poweroff</literal>,
+                <literal>reboot</literal> or
+                <literal>kexec</literal>, depending on the chosen
                 action. All executables in this directory are executed
                 in parallel, and execution of the action is not
                 continued before all executables finished.</para>
@@ -101,7 +107,7 @@
                 <filename>systemd-halt.service</filename> (and the
                 related units) should never be executed
                 directly. Instead, trigger system shutdown with a
-                command such as "<literal>systemctl halt</literal>" or
+                command such as <literal>systemctl halt</literal> or
                 suchlike.</para>
         </refsect1>