docs: add note about line continuation

Closes: #1668
[ci skip]

diff --git a/doc/manual.xml.head b/doc/manual.xml.head
index 5bd3fc0cc3857dd37639d98a8a0005e1919cf0ca..9fd22c9e8249aaf7bc94a6c9cf7e1c0f9cc99467 100644 (file)
--- a/doc/manual.xml.head
+++ b/doc/manual.xml.head
@@ -3601,6 +3601,15 @@ over several lines"
 </screen>
 
       </example>
+      <note>
+        <para>
+          Using <quote>\</quote> at the end of a line <emphasis>only</emphasis>
+          removes the newline character.
+        </para>
+        <para>
+          Any leading whitespace on the following lines will be part of the configuration.
+        </para>
+      </note>
       <para>
         It is also possible to substitute the output of a Unix command in an
         initialization file. This is accomplished by enclosing the command in