Document that changing directories unloads all modules.
beginning of <replaceable>dir</replaceable> will be replaced
by the contents of the environment variable
<literal>HOME</literal>.</para>
+
+ <para>NOTE: changing directories causes all currently loaded
+ modules to be unloaded. This is because the search path is
+ usually expressed using relative directories, and changing
+ the search path in the middle of a session is not
+ supported.</para>
</listitem>
</varlistentry>