man: don't claim we'd set XDG_SEAT and XDG_VTNR as part of service management

Previously, reading through systemd.exec(5) one might get the idea that
XDG_SEAT and XDG_VTNR are part of the service management logic, but they
are not, they are only set if pam_systemd is part of a PAM stack an
pam_systemd is used.

Hence, let's drop these env vars from the list of env vars, and instead
add a paragraph after the list mentioning that pam_systemd might add
more systemd-specific env vars if included in the PAM stack for a
service that uses PAMName=.
This commit is contained in:
Lennart Poettering 2018-04-24 11:51:21 +02:00
parent 0a233ba179
commit 46b073298f
1 changed files with 15 additions and 20 deletions

View File

@ -1972,7 +1972,9 @@ StandardInputData=SWNrIHNpdHplIGRhIHVuJyBlc3NlIEtsb3BzLAp1ZmYgZWVtYWwga2xvcHAncy
<listitem><para>Variables read from files specified via <varname>EnvironmentFile=</varname> in the unit file</para></listitem>
<listitem><para>Variables set by any PAM modules in case <varname>PAMName=</varname> is in effect, cf. <citerefentry project='man-pages'><refentrytitle>pam_env</refentrytitle><manvolnum>8</manvolnum></citerefentry></para></listitem>
<listitem><para>Variables set by any PAM modules in case <varname>PAMName=</varname> is in effect,
cf. <citerefentry
project='man-pages'><refentrytitle>pam_env</refentrytitle><manvolnum>8</manvolnum></citerefentry></para></listitem>
</itemizedlist>
<para>If the same environment variables are set by multiple of these sources, the later source — according to the
@ -1980,7 +1982,8 @@ StandardInputData=SWNrIHNpdHplIGRhIHVuJyBlc3NlIEtsb3BzLAp1ZmYgZWVtYWwga2xvcHAncy
<varname>UnsetEnvironment=</varname> are removed again from the compiled environment variable list, immediately
before it is passed to the executed process.</para>
<para>The following select environment variables are set by the service manager itself for each invoked process:</para>
<para>The following select environment variables are set or propagated by the service manager for each invoked
process:</para>
<variablelist class='environment-variables'>
<varlistentry>
@ -2031,24 +2034,11 @@ StandardInputData=SWNrIHNpdHplIGRhIHVuJyBlc3NlIEtsb3BzLAp1ZmYgZWVtYWwga2xvcHAncy
<varlistentry>
<term><varname>$XDG_RUNTIME_DIR</varname></term>
<listitem><para>The directory for volatile state. Set for the
user <command>systemd</command> instance, and also in user
sessions. See
<citerefentry><refentrytitle>pam_systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>$XDG_SESSION_ID</varname></term>
<term><varname>$XDG_SEAT</varname></term>
<term><varname>$XDG_VTNR</varname></term>
<listitem><para>The identifier of the session, the seat name,
and virtual terminal of the session. Set by
<citerefentry><refentrytitle>pam_systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
for login sessions. <varname>$XDG_SEAT</varname> and
<varname>$XDG_VTNR</varname> will only be set when attached to
a seat and a tty.</para></listitem>
<listitem><para>The directory to use for runtime objects (such as IPC objects) and volatile state. Set for all
services run by the user <command>systemd</command> instance, as well as any system services that use
<varname>PAMName=</varname> with a PAM stack that includes <command>pam_systemd</command>. See below and
<citerefentry><refentrytitle>pam_systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry> for more
information.</para></listitem>
</varlistentry>
<varlistentry>
@ -2302,6 +2292,11 @@ StandardInputData=SWNrIHNpdHplIGRhIHVuJyBlc3NlIEtsb3BzLAp1ZmYgZWVtYWwga2xvcHAncy
</listitem>
</varlistentry>
</variablelist>
<para>For system services, when <varname>PAMName=</varname> is enabled and <command>pam_systemd</command> is part
of the selected PAM stack, additional environment variables defined by systemd may be set for
services. Specifically, these are <varname>$XDG_SEAT</varname>, <varname>$XDG_VTNR</varname>, see
<citerefentry><refentrytitle>pam_systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry> for details.</para>
</refsect1>
<refsect1>