</listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>GuessMainPID=</varname></term>
+
+ <listitem><para>Takes a boolean value
+ that specifies whether systemd should
+ try to guess the main PID of a service
+ should if it cannot be determined
+ reliably. This option is ignored
+ unless <option>Type=forking</option>
+ is set and <option>PIDFile=</option>
+ is unset because for the other types
+ or with an explicitly configured PID
+ file the main PID is always known. The
+ guessing algorithm might come to
+ incorrect conclusions if a daemon
+ consists of more than one process. If
+ the main PID cannot be determined
+ failure detection and automatic
+ restarting of a service will not work
+ reliably. Defaults to
+ <option>yes</option>.</para>
+ </listitem>
+ </varlistentry>
+
<varlistentry>
<term><varname>PIDFile=</varname></term>
daemon. Use of this option is
recommended for services where
<varname>Type=</varname> is set to
- <option>forking</option>.</para>
+ <option>forking</option>. systemd will
+ read the PID of the main process of
+ the daemon after start-up of the
+ service. systemd will not write to the
+ file configured here.</para>
</listitem>
</varlistentry>