Add documentation on thread tree characters and config vars.

diff --git a/doc/manual.xml.head b/doc/manual.xml.head
index 9c9fda2d691f6b6e3cf9299c60e4da4005b7c4e4..76778f423ac4cff58c4619e3595de2b61e243ec5 100644 (file)
--- a/doc/manual.xml.head
+++ b/doc/manual.xml.head
@@ -929,6 +929,56 @@ and <emphasis>pager</emphasis> modes as shown in
 </tgroup>
 </table>
 
+<para>
+In the <emphasis>index</emphasis>, the subject of threaded children
+messages will be prepended with thread tree characters.  By default,
+the subject itself will not be duplicated unless <link
+linkend="hide-thread-subject">$hide_thread_subject</link> is unset.
+Special characters will be added to the thread tree as detailed in
+<xref linkend="tab-thread-chars"/>.
+</para>
+
+<table id="tab-thread-chars">
+  <title>Special Thread Characters</title>
+  <tgroup cols="3">
+    <thead>
+      <row>
+        <entry>Character</entry>
+        <entry>Description</entry>
+        <entry>Notes</entry>
+      </row>
+    </thead>
+    <tbody>
+      <row>
+        <entry>&amp;</entry>
+        <entry>hidden message</entry>
+        <entry>see <link linkend="hide-limited">$hide_limited</link> and
+        <link linkend="hide-top-limited">$hide_top_limited</link></entry>
+      </row>
+      <row>
+        <entry>?</entry>
+        <entry>missing message</entry>
+        <entry>see <link linkend="hide-missing">$hide_missing</link> and
+        <link linkend="hide-top-missing">$hide_top_missing</link></entry>
+      </row>
+      <row>
+        <entry>*</entry>
+        <entry>psuedo thread</entry>
+        <entry>see <link linkend="strict-threads">$strict_threads</link>;
+        not displayed when
+        <link linkend="narrow-tree">$narrow_tree</link> is set</entry>
+      </row>
+      <row>
+        <entry>=</entry>
+        <entry>duplicate thread</entry>
+        <entry>see <link linkend="duplicate-threads">$duplicate_threads</link>;
+        not displayed when
+        <link linkend="narrow-tree">$narrow_tree</link> is set</entry>
+      </row>
+    </tbody>
+  </tgroup>
+</table>
+
 <para>
 Collapsing a thread displays only the first message in the thread and
 hides the others. This is useful when threads contain so many messages