man,units: link up new documentation about temporary directories

man/file-hierarchy.xml

@@ -128,24 +128,22 @@
 
       <varlistentry>
         <term><filename>/tmp/</filename></term>
-        <listitem><para>The place for small temporary files. This
+        <listitem><para>The place for small temporary files. This directory is usually mounted as a
-        directory is usually mounted as a <literal>tmpfs</literal>
+        <literal>tmpfs</literal> instance, and should hence not be used for larger files. (Use
-        instance, and should hence not be used for larger files. (Use
+        <filename>/var/tmp/</filename> for larger files.) Since the directory is accessible to other users of
-        <filename>/var/tmp/</filename> for larger files.) Since the
+        the system, it is essential that this directory is only written to with the <citerefentry
-        directory is accessible to other users of the system, it is
+        project='man-pages'><refentrytitle>mkstemp</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
-        essential that this directory is only written to with the
+        <citerefentry
-        <citerefentry project='man-pages'><refentrytitle>mkstemp</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+        project='man-pages'><refentrytitle>mkdtemp</refentrytitle><manvolnum>3</manvolnum></citerefentry> and
-        <citerefentry project='man-pages'><refentrytitle>mkdtemp</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+        related calls. This directory is usually flushed at boot-up. Also, files that are not accessed within
-        and related calls. This directory is usually flushed at
+        a certain time are usually automatically deleted. If applications find the environment variable
-        boot-up. Also, files that are not accessed within a certain
+        <varname>$TMPDIR</varname> set, they should prefer using the directory specified in it over directly
-        time are usually automatically deleted. If applications find
+        referencing <filename>/tmp/</filename> (see <citerefentry
-        the environment variable <varname>$TMPDIR</varname> set, they
+        project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry> and
-        should prefer using the directory specified in it over
-        directly referencing <filename>/tmp/</filename> (see
-        <citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>
-        and
         <ulink url="http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html#tag_08_03">IEEE
-        Std 1003.1</ulink> for details).</para></listitem>
+        Std 1003.1</ulink> for details). For further details about this directory, see <ulink
+        url="https://systemd.io/TEMPORARY_DIRECTORIES">Using /tmp/ And /var/tmp/
+        Safely</ulink>.</para></listitem>
       </varlistentry>
 
     </variablelist>
@@ -337,24 +335,22 @@
 
       <varlistentry>
         <term><filename>/var/tmp/</filename></term>
-        <listitem><para>The place for larger and persistent temporary
+        <listitem><para>The place for larger and persistent temporary files. In contrast to
-        files. In contrast to <filename>/tmp/</filename>, this directory
+        <filename>/tmp/</filename>, this directory is usually mounted from a persistent physical file system
-        is usually mounted from a persistent physical file system and
+        and can thus accept larger files. (Use <filename>/tmp/</filename> for smaller files.) This directory
-        can thus accept larger files. (Use <filename>/tmp/</filename>
+        is generally not flushed at boot-up, but time-based cleanup of files that have not been accessed for
-        for smaller files.) This directory is generally not flushed at
+        a certain time is applied. The same security restrictions as with <filename>/tmp/</filename> apply,
-        boot-up, but time-based cleanup of files that have not been
+        and hence only <citerefentry
-        accessed for a certain time is applied. The same security
+        project='man-pages'><refentrytitle>mkstemp</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
-        restrictions as with <filename>/tmp/</filename> apply, and
+        <citerefentry
-        hence only
+        project='man-pages'><refentrytitle>mkdtemp</refentrytitle><manvolnum>3</manvolnum></citerefentry> or
-        <citerefentry project='man-pages'><refentrytitle>mkstemp</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+        similar calls should be used to make use of this directory.  If applications find the environment
-        <citerefentry project='man-pages'><refentrytitle>mkdtemp</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+        variable <varname>$TMPDIR</varname> set, they should prefer using the directory specified in it over
-        or similar calls should be used to make use of this directory.
+        directly referencing <filename>/var/tmp/</filename> (see <citerefentry
-        If applications find the environment variable
+        project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry> for
-        <varname>$TMPDIR</varname> set, they should prefer using the
+        details). For further details about this directory, see <ulink
-        directory specified in it over directly referencing
+        url="https://systemd.io/TEMPORARY_DIRECTORIES">Using /tmp/ And /var/tmp/
-        <filename>/var/tmp/</filename> (see
+        Safely</ulink>.</para></listitem>
-        <citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>
-        for details). </para></listitem>
       </varlistentry>
 
     </variablelist>

units/tmp.mount

@@ -9,7 +9,8 @@
 
 [Unit]
 Description=Temporary Directory (/tmp)
-Documentation=man:hier(7)
+Documentation=https://systemd.io/TEMPORARY_DIRECTORIES
+Documentation=man:file-hierarchy(7)
 Documentation=https://www.freedesktop.org/wiki/Software/systemd/APIFileSystems
 ConditionPathIsSymbolicLink=!/tmp
 DefaultDependencies=no