man: reword description of "-" for sysctl.d

Follow-up for e08be64937.

diff --git a/man/sysctl.d.xml b/man/sysctl.d.xml
index 21ef6de..4932948 100644 (file)
--- a/man/sysctl.d.xml
+++ b/man/sysctl.d.xml
@@ -59,9 +59,11 @@
     <filename>/proc/sys/net/ipv4/conf/enp3s0.200/forwarding</filename>.
     </para>
 
-    <para>If a variable assignment is prefixed with a single <literal>-</literal> character, any attempts to
-    set it that fail will be ignored (though are logged). Moreover, any access permission errors, and
-    attempts to write variables not defined on the local system are ignored (and logged) too.</para>
+    <para>Any access permission errors and attempts to write variables not defined on the local system are
+    logged, but do not cause the the service to fail. Moreover, if a variable assignment is prefixed with a
+    single <literal>-</literal> character, failure to set the variable will be logged, but will not cause the
+    service to fail. All other errors when setting variables cause the service to return failure at the end
+    (other variables are still processed).</para>
 
     <para>The settings configured with <filename>sysctl.d</filename>
     files will be applied early on boot. The network