lfs-book-zh_CN/chapter01/othermodes.xml

<sect2>
<title>Other list modes</title>

<para>
The modes that can be set by a user require to send an email to
<ulink url="mailto:listar@linuxfromscratch.org">
listar@linuxfromscratch.org</ulink>. The modes themselves are set by writing
the appropriate commands in the subject headers of the message.
</para>

<para>
As the name implies, the <emphasis>Set command</emphasis> tells what
to write to set a mode. The <emphasis>Unset command</emphasis> tells
what to write to unset a mode.
</para>

<para>
The listname in the example subject headers should be replaced with the 
listname to which 
the mode is going to be applied to. If more than one mode is to be set (to
the same list or multiple lists) with one email, this can be done by
leaving the subject header blank and write all the commands in the body of 
the message instead.
</para>

</sect2>

<sect2>
<title>Digests</title>

<literallayout>
Set command: <emphasis>set listname digest</emphasis>
Unset command: <emphasis>unset listname digest</emphasis>
</literallayout>

<para>
All lists have the digest mode available which can be set after a user
has subscribed to a list. Being in digest mode will
cause to stop receiving individual messages as they are posted to
the list and instead send one email daily containing all
the messages posted to the list during that day.
</para>

<para>
There is a second digest mode called digest2. When a user is set to this
mode he will receive the daily digests but will also continue to
receive the individual messages to the lists as they are posted. To
set this mode <emphasis>digest2</emphasis> has to be written instead of
<emphasis>digest</emphasis> in the subject header.
</para>

</sect2>

<sect2>
<title>Vacation</title>

<literallayout>
Set command: <emphasis>set listname vacation</emphasis>
Unset command: <emphasis>unset listname vacation</emphasis>
</literallayout>

<para>
If a user is going to be away for a while or wishes to stop receiving
messages from the lists but doesn't want to unsubscribe, he can set
to vacation mode. This has the same effect as unsubscribing,
but without having to go through the unsubscribe process and
then later through the subscribe process again.
</para>

</sect2>