+ system manager is compiled for). If
+ running in user mode and this option
+ is used,
+ <varname>NoNewPrivileges=yes</varname>
+ is implied. Note that setting this
+ option to a non-empty list implies
+ that <constant>native</constant> is
+ included too. By default, this option
+ is set to the empty list, i.e. no
+ architecture system call filtering is
+ applied.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>RestrictAddressFamilies=</varname></term>
+
+ <listitem><para>Restricts the set of
+ socket address families accessible to
+ the processes of this unit. Takes a
+ space-separated list of address family
+ names to whitelist, such as
+ <constant>AF_UNIX</constant>,
+ <constant>AF_INET</constant> or
+ <constant>AF_INET6</constant>. When
+ prefixed with <constant>~</constant>
+ the listed address families will be
+ applied as blacklist, otherwise as
+ whitelist. Note that this restricts
+ access to the
+ <citerefentry><refentrytitle>socket</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+ system call only. Sockets passed into
+ the process by other means (for
+ example, by using socket activation
+ with socket units, see
+ <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>)
+ are unaffected. Also, sockets created
+ with <function>socketpair()</function>
+ (which creates connected AF_UNIX
+ sockets only) are unaffected. Note
+ that this option has no effect on
+ 32-bit x86 and is ignored (but works
+ correctly on x86-64). If running in user
+ mode and this option is used,
+ <varname>NoNewPrivileges=yes</varname>
+ is implied. By default, no
+ restriction applies, all address
+ families are accessible to
+ processes. If assigned the empty
+ string, any previous list changes are
+ undone.</para>
+
+ <para>Use this option to limit
+ exposure of processes to remote
+ systems, in particular via exotic
+ network protocols. Note that in most
+ cases, the local
+ <constant>AF_UNIX</constant> address
+ family should be included in the
+ configured whitelist as it is
+ frequently used for local
+ communication, including for
+ <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+ logging.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>Personality=</varname></term>
+
+ <listitem><para>Controls which
+ kernel architecture
+ <citerefentry><refentrytitle>uname</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+ shall report, when invoked by unit
+ processes. Takes one of
+ <constant>x86</constant> and
+ <constant>x86-64</constant>. This is
+ useful when running 32-bit services on
+ a 64-bit host system. If not specified,
+ the personality is left unmodified and
+ thus reflects the personality of the
+ host system's
+ kernel.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>RuntimeDirectory=</varname></term>
+ <term><varname>RuntimeDirectoryMode=</varname></term>
+
+ <listitem><para>Takes a list of
+ directory names. If set, one or more
+ directories by the specified names
+ will be created below
+ <filename>/run</filename> (for system
+ services) or below
+ <varname>$XDG_RUNTIME_DIR</varname>
+ (for user services) when the unit is
+ started, and removed when the unit is
+ stopped. The directories will have the
+ access mode specified in
+ <varname>RuntimeDirectoryMode=</varname>,
+ and will be owned by the user and
+ group specified in
+ <varname>User=</varname> and
+ <varname>Group=</varname>. Use this to
+ manage one or more runtime directories
+ of the unit and bind their lifetime to
+ the daemon runtime. The specified
+ directory names must be relative, and
+ may not include a
+ <literal>/</literal>, i.e. must refer
+ to simple directories to create or
+ remove. This is particularly useful
+ for unprivileged daemons that cannot
+ create runtime directories in
+ <filename>/run</filename> due to lack
+ of privileges, and to make sure the
+ runtime directory is cleaned up
+ automatically after use. For runtime
+ directories that require more complex
+ or different configuration or lifetime
+ guarantees, please consider using
+ <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>