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-rw-r--r--man/systemd.exec.xml60
1 files changed, 32 insertions, 28 deletions
diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml
index bf82326096..bcedebd5bb 100644
--- a/man/systemd.exec.xml
+++ b/man/systemd.exec.xml
@@ -160,14 +160,14 @@
use. However, UID/GIDs are recycled after a unit is terminated. Care should be taken that any processes running
as part of a unit for which dynamic users/groups are enabled do not leave files or directories owned by these
users/groups around, as a different unit might get the same UID/GID assigned later on, and thus gain access to
- these files or directories. If <varname>DynamicUser=</varname> is enabled, <varname>PrivateTmp=</varname> is
- implied. This ensures that the lifetime of temporary files created by the executed processes is bound to the
- runtime of the service, and hence the lifetime of the dynamic user/group. Since <filename>/tmp</filename> and
- <filename>/var/tmp</filename> are usually the only world-writable directories on a system this ensures that a
- unit making use of dynamic user/group allocation cannot leave files around after unit termination. Use
- <varname>RuntimeDirectory=</varname> (see below) in order to assign a writable runtime directory to a service,
- owned by the dynamic user/group and removed automatically when the unit is terminated. Defaults to
- off.</para></listitem>
+ these files or directories. If <varname>DynamicUser=</varname> is enabled, <varname>RemoveIPC=</varname> and
+ <varname>PrivateTmp=</varname> are implied. This ensures that the lifetime of IPC objects and temporary files
+ created by the executed processes is bound to the runtime of the service, and hence the lifetime of the dynamic
+ user/group. Since <filename>/tmp</filename> and <filename>/var/tmp</filename> are usually the only
+ world-writable directories on a system this ensures that a unit making use of dynamic user/group allocation
+ cannot leave files around after unit termination. Use <varname>RuntimeDirectory=</varname> (see below) in order
+ to assign a writable runtime directory to a service, owned by the dynamic user/group and removed automatically
+ when the unit is terminated. Defaults to off.</para></listitem>
</varlistentry>
<varlistentry>
@@ -186,6 +186,18 @@
</varlistentry>
<varlistentry>
+ <term><varname>RemoveIPC=</varname></term>
+
+ <listitem><para>Takes a boolean parameter. If set, all System V and POSIX IPC objects owned by the user and
+ group the processes of this unit are run as are removed when the unit is stopped. This setting only has an
+ effect if at least one of <varname>User=</varname>, <varname>Group=</varname> and
+ <varname>DynamicUser=</varname> are used. It has no effect on IPC objects owned by the root user. Specifically,
+ this removes System V semaphores, as well as System V and POSIX shared memory segments and message queues. If
+ multiple units use the same user or group the IPC objects are removed when the last of these units is
+ stopped. This setting is implied if <varname>DynamicUser=</varname> is set.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
<term><varname>Nice=</varname></term>
<listitem><para>Sets the default nice level (scheduling
@@ -920,27 +932,19 @@
<varlistentry>
<term><varname>PrivateTmp=</varname></term>
- <listitem><para>Takes a boolean argument. If true, sets up a
- new file system namespace for the executed processes and
- mounts private <filename>/tmp</filename> and
- <filename>/var/tmp</filename> directories inside it that is
- not shared by processes outside of the namespace. This is
- useful to secure access to temporary files of the process, but
- makes sharing between processes via <filename>/tmp</filename>
- or <filename>/var/tmp</filename> impossible. If this is
- enabled, all temporary files created by a service in these
- directories will be removed after the service is stopped.
- Defaults to false. It is possible to run two or more units
- within the same private <filename>/tmp</filename> and
- <filename>/var/tmp</filename> namespace by using the
+ <listitem><para>Takes a boolean argument. If true, sets up a new file system namespace for the executed
+ processes and mounts private <filename>/tmp</filename> and <filename>/var/tmp</filename> directories inside it
+ that is not shared by processes outside of the namespace. This is useful to secure access to temporary files of
+ the process, but makes sharing between processes via <filename>/tmp</filename> or <filename>/var/tmp</filename>
+ impossible. If this is enabled, all temporary files created by a service in these directories will be removed
+ after the service is stopped. Defaults to false. It is possible to run two or more units within the same
+ private <filename>/tmp</filename> and <filename>/var/tmp</filename> namespace by using the
<varname>JoinsNamespaceOf=</varname> directive, see
- <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
- for details. Note that using this setting will disconnect
- propagation of mounts from the service to the host
- (propagation in the opposite direction continues to work).
- This means that this setting may not be used for services
- which shall be able to install mount points in the main mount
- namespace.</para></listitem>
+ <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
+ details. Note that using this setting will disconnect propagation of mounts from the service to the host
+ (propagation in the opposite direction continues to work). This means that this setting may not be used for
+ services which shall be able to install mount points in the main mount namespace. This setting is implied if
+ <varname>DynamicUser=</varname> is set.</para></listitem>
</varlistentry>
<varlistentry>