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<HTML><HEAD><TITLE>Alpine Technical Notes: Notes on Configuration and 
Preferences</TITLE></HEAD><BODY>
<H1>Notes on Configuration and Preferences</H1>

<H2><A NAME="fkey">Alpine in Function Key Mode</A></H2>

The standard <EM>Alpine</EM> uses alphabetic keys for most commands, and control keys
in the composer.  Despite possible appearances, the current bindings are
the result of much discussion and thought.  All the commands in the
composer are single control characters.  This keeps things very neat and
simple for users.  Two character commands in the composer are a
possibility, but we're trying to avoid them because of the added
complexity for the user.  <P>

<EM>Alpine</EM> can also operate in a function-key mode.  To go into this mode invoke
<EM>alpine -k</EM> or (on some UNIX systems) <EM>alpinef.</EM> On a UNIX
system, you can link or copy the <EM>Alpine</EM> executable to
<EM>alpinef</EM> to install <EM>alpinef.</EM> Alternatively, users and systems
administrators can set the <EM>use-function-keys</EM> feature in the
personal or system-wide <EM>Alpine</EM> configuration file.
The command menus at the
bottom of the screen will show <EM>F1-F12 </EM>instead of the alphabetic
commands.  In addition, the help screens will be written in terms of
function keys and not alphabetic keys.  <P>

One of the results of using <EM>Alpine</EM> in function-key mode is that users can
only choose from twelve commands at any given time.  In alphabetic-key
mode, a user can press a key for a command (say, q to quit) and that
command can be fulfilled.  In function-key mode, the command must be
visible on the bottom key-menu in order to be used.  There are some
screens where four screens of commands are operational;
function-key users can get to all of them, just not all at once.  <P>

<HR>

<H2><A NAME="domain">Domain Settings</A></H2>

<EM>Alpine</EM> uses the default domain for a few different tasks.  First, it is
tacked onto the user-id for outgoing email.  Second, it is tacked onto all
"local" (unqualified) addresses in the "To:" or "Cc:" fields of messages
being composed (unless they are found in the address book or on an
LDAP server). The domain
name is also used to generate message-id lines for each outgoing message
and to allow <EM>Alpine</EM> to check if an address is that of the current <EM>Alpine</EM> user. 
<P>

<EM>Alpine</EM> determines the domain name according
to whichever of these it finds. 
The list here is in decreasing order of precedence. 

<OL>

<LI> Value of the variable
<A HREF="config.html#user-domain"><EM>user-domain</EM></A>
in the system fixed configuration file

<LI> Value of the variable <EM>user-domain</EM> in the personal
configuration file

<LI> Value of the variable <EM>user-domain</EM> in the system-wide
configuration file

<LI> Value from an external database (DNS, <CODE>/etc/hosts</CODE>, NIS) as
modified by a system fixed configuration file if
<A HREF="config.html#use-only"><EM>use-only-domain-name</EM></A>
set to <EM>yes</EM>

<LI> Value from an external database (DNS, <CODE>/etc/hosts</CODE>, NIS) as
modified by a personal configuration file if <EM>use-only-domain-name</EM>
set to <EM>yes</EM>

<LI> Value from an external database (DNS, <CODE>/etc/hosts</CODE>, NIS) as
modified by a system configuration file if <EM>use-only-domain-name</EM>
set to <EM>yes</EM>

<LI> Unmodified value (host name) from an external database <P>

</OL>

<P> The easiest way for this system to work is for <EM>PC-Alpine</EM>
users and UNIX <EM>Alpine</EM> system administrators to
set the <EM>user-domain</EM> variable.  The
variable <EM>use-only-domain-name</EM> is helpful if your site
supports/requires hostless addressing, but for some reason you don't want
to use the <EM>user-domain</EM> variable.  <P> 

<HR>

<H2><A NAME="collections">Syntax for Collections</A></H2>

In many environments, it is quite common to have collections of archived
mail on various hosts around the network.  Using the folder collections
facility in <EM>Alpine</EM>, access to these archives is just as simple as access to
folders on <EM>Alpine</EM>'s local disk.  <P>

"Collection" is the word we use in <EM>Alpine</EM> to describe a set of folders.  A
collection corresponds loosely to a "directory" containing mail folders. 
Folders within a defined collection can be manipulated (opened, saved-to,
etc) using just their simple name.  Any number of folder collections can
be defined, and <EM>Alpine</EM> will adjust its menus and prompts to help navigate
them.  <P>

The way collections are defined in <EM>Alpine</EM> is with the
<A HREF="config.html#fold-coll"><EM>folder-collections</EM></A>
variable in the <EM>Alpine</EM> configuration file. 
<EM>Folder-collections</EM> takes a list of one or more collections, each
(optionally) preceded by a user-defined logical name (label).  Once
collections are defined, <EM>Alpine</EM> adjusts its menus and behavior to allow
choosing files by their simple name within the collection.
<P>

Consider the following: 

<PRE>
   folder-collections=	Local-Mail	C:\MAIL\[],
			Remote-Mail	{imap.u.example.edu}mail/[]
</PRE>
<P>

The example shows two collections defined (a comma separated list;
newlines in the list are OK if there's one or more spaces before the next
entry), one local and one remote.  Each collection is a space-delimited
pair of elements-first an optional logical-name and second the collection
specifier.  The logical-name can have spaces if it has quotes around it
(but keeping the logical name short and descriptive works best).  <EM>Alpine</EM>
will use the logical-name (if provided) to reference all folders in the
collection, so the user never has to see the ugliness of the collection
specifier.  <P>

The collection specifier can be thought of as an extended IMAP format (see
the <A HREF="#remote-folders"><EM>Remote Folders</EM></A> section
for a description of IMAP format names). 
Basically, a pair of square-brackets are placed in the fully qualified
IMAP path where the simple folder name (the part without the host name and
path) would appear.  Like IMAP, the path can be either fully qualified
(i.e., with a leading '/') or relative to your home directory.  <P>

An advanced feature of this notation is that a pattern within the square
brackets allows the user to define a collection to be a subset of a
directory.  For example, a collection defined with the specifier: 

<PRE>
	M-Mail		C:MAIL/[m*]<BR>
</PRE>

will provide a view in the folder lister of all folders in the PC's
"C:MAIL" directory that start with the letter 'm' (case insensitive under
DOS, of course).  Further, the wildcard matching will honor characters
trailing the '*' in the pattern.  <P>

From within <EM>Alpine</EM>, the "Folder List" display will be adjusted to allow
browsing of the folders in any defined collection.  Even more, you'll
notice in the <EM>Goto</EM> and <EM>Save</EM> commands a pair of
sub-commands to rotate
through the list of logical collection names, so only a simple name need
be input in order to operate on a folder in any collection.  <P>

The first collection specified in the <EM>folder-collections</EM> has
special significance.  That folder is the "default collection for saves". 
By default, in cases where the user does not specify which
collection should be used to <EM>Save</EM> a message,
the default collection for saves will be used.
Also, if the <A HREF="config.html#def-fcc"><EM>default-fcc</EM></A>
is a relative file name, then it is relative
to the default collection for saves. (See also
<A HREF="config.html#saved-msg-name"><EM>saved-msg-name-rule</EM></A>. <P>

The notion of collections encompasses both email folders and news reading. 
The variable <A HREF="config.html#news-coll"><EM>news-collections</EM></A>
uses nearly the same format as <EM>folder-collections</EM>.
Newsgroups can be defined for convenient
access via either IMAP or NNTP. There are advantages and disadvantages to
both access methods. In the IMAP case, your news environment state is
maintained on the server and, thus, will be seen by any client.  The
downside is that, at the moment, you must have an account on the server. 
In the NNTP case, server access is mostly anonymous and no
state/accounting need be maintained on it.  The downside is that each
client, for now, must individually maintain news environment state.  <P>

An example pinerc entry might be: 

<PRE>
     news-collections=	Remote-State	{news.u.example.edu}#news.[],
			Local-State	{news.u.example.edu/nntp}#news.[]
</PRE>

Only newsgroups to which you are subscribed are included in the collection. <P>

The pattern matching facility can be applied so as to define a news 
collection which is a subset of all the newsgroups you subscribe to.  For 
example, this could be a valid collection: 

<PRE>
			Newsfeed-News	{news.u.example.edu/nntp}#news.[clari.*]
</PRE>
<P>

Collection handling is a tough problem to solve in a general way, and the
explanation of the syntax is a bit ugly.  The upside is, hopefully, that
for a little complexity in the <EM>Alpine</EM> configuration file you get simple
management of multiple folders in diverse locations.  <P>

Collection setup is handled by the
<EM>Setup/collectionList</EM> screen.  <P>

<HR>

<H2><A NAME="remote-folders">Syntax for Folder Names</A></H2>

Remote folders are distinguished from local folders by a leading host name
bracketed by '{' and '}'.  The path and folder name immediately following
the closing bracket, '}', is interpreted by the remote server and is in a
form compatible with that server (i.e., path delimiters and naming syntax
relative to that server).
<P>

The full syntax for a <EM>Alpine</EM> folder name looks like

<P>
<CENTER><SAMP>[{&lt;remote-specification&gt;}][#&lt;namespace&gt;]&lt;namespace-specific-part&gt;</SAMP></CENTER>
<P>

The square brackets ([]) mean that the part is optional.
<P>

If there is no remote-specification, then the folder name is interpreted
locally on the computer running <EM>Alpine</EM>.
Local folder names depend on the operating system used by the computer 
running <EM>Alpine</EM>, as well as the configuration of that system.  For example,
&quot;C:&#92;ALPINE&#92;FOLDERS&#92;OCT-94&quot; might exist on a PC, and
&quot;~/mail/september-1994&quot; might be a reasonable folder name on a
system running Unix.

<P>
<EM>Alpine</EM> users have the option of using folders which are stored on some other
computer.  <EM>Alpine</EM> accesses remote folders via IMAP (the Internet Message
Access Protocol), or in the case of news, via NNTP (the Network News
Transport Protocol).  To be able to access remote folders in <EM>Alpine</EM>, the
remote host must be running the appropriate server software (imapd or
nntpd) and you must correctly specify the name of the folder to <EM>Alpine</EM>,
including the domain name of the remote machine. For example,
<P>
<CENTER><SAMP>&#123;monet.art.example.com}INBOX</SAMP></CENTER>
<P>
could be a remote folder specification, and so could
<P>
<CENTER><SAMP>&#123;unixhost.art.example.com}~/mail/september-1994</SAMP></CENTER>
and
<P>
<CENTER><SAMP>&#123;winhost.art.example.com}&#92;mymail&#92;SEP-94</SAMP></CENTER>
<P>
Note that in the case of remote folders, the directory/file path in the specification is 
determined by the operating system of the remote computer, <B>not</B> by
the operating system of the computer on which you are running <EM>Alpine</EM>.
<P>
As you can tell, the name of the computer is in &#123;} brackets
followed immediately by the name of the folder.  (In each of these cases the
optional namespace is missing.)  If, as in these
examples, there is no remote access protocol specified, then IMAP is
assumed.  Check
<A HREF="#server-name-syntax"><EM>Server Name Syntax</EM></A>
for a more detailed look at what options can be placed between the brackets.
If there are no brackets at all, then the folder name is interpreted locally
on the computer on which you are running <EM>Alpine</EM>.

<P>
To the right of the brackets when a server name is present, or at the
start of the foldername if no server is present, the sharp sign,
&quot;#&quot;, holds special meaning.  It indicates a folder name
outside the area reserved for your personal folders.  In fact, it's
used to indicate both the name of the folder, and a special phrase
telling <EM>Alpine</EM> how to interpret the name that follows.

<P>
So, for example, <EM>Alpine</EM> can be used to access a newsgroup that might be 
available on your computer using:
<P>
<CENTER><SAMP>#news.comp.mail.pine</SAMP></CENTER>
<P>
The sharp sign indicates the folder name is outside your personal
folder area.  The &quot;news.&quot; phrase after it tells <EM>Alpine</EM> to 
interpret the remainder of the name as a newsgroup.

<P>
Similarly, to access a newsgroup on your IMAP server, you might
use something like:
<P>
<CENTER><SAMP>&#123;wharhol.art.example.com}#news.comp.mail.misc</SAMP></CENTER>

<P>
There are a number of such special phrases (or &quot;namespaces&quot;)
available.  For a more detailed explanation read about
<A HREF="#folder-namespaces"><EM>Namespaces</EM></A>.

<P>
Note that &quot;INBOX&quot; has special meaning in both local and remote folder
names.  The name INBOX refers to your &quot;principal incoming
message folder&quot; and will be mapped to the actual file name used for your
INBOX on any given host.  Therefore, a name like
&quot;&#123;xxx.art.example.com}INBOX&quot; refers to whatever file is used to
store incoming mail for you on that particular host.
<P>

<HR>

<H2><A NAME="server-name-syntax">Server Name Syntax</A></H2>

This section describes the syntax which may be used for server names
which may be associated with remote folders or SMTP servers.

<P>
A server name is the hostname of the server.
It's a good idea to use the host's fully-qualified network name.

<P>
<CENTER><SAMP>foo.example.com</SAMP></CENTER>
<P>

However, IP addresses are allowed if surrounded
with square-brackets.

<P>
<CENTER><SAMP>[127.0.0.1]</SAMP></CENTER>
<P>

An optional network port number may be supplied by appending
a colon (:) followed by the port number
to the server name.
By default, the IMAP port number, 143, is used.

<P>
<CENTER><SAMP>foo.example.com:port</SAMP></CENTER>
<P>

Besides server name and optional port number, various other optional
parameters may be supplied that alter <EM>Alpine</EM>'s interaction with the server.
A parameter is supplied by appending a slash (/) character followed by
the parameter's name and,
depending on the particular parameter, the value assigned to that
name, to the server name (and optional port number).
Parameter names are <EM>not</EM> case sensitive.
Currently supported parameters include:

<DL>

<DT>User</DT>
<DD>This parameter requires an associated value, and is intended to
provide the username identifier with which to establish the server
connection.
If your SMTP server offers SMTP AUTH authentication, adding this 
parameter to the
<A HREF="config.html#smtp-server"><EM>SMTP-Server</EM></A>
option will cause <EM>Alpine</EM> to attempt to authenticate to the server using the
supplied username.
Similarly, if your NNTP server offers NNTP &quot;AUTHINFO SASL&quot;
or &quot;AUTHINFO USER&quot; authentication, adding this parameter to the
<A HREF="config.html#nntp-server"><EM>NNTP-Server</EM></A>
option (or to the server name for any folder collection using NNTP)
will cause <EM>Alpine</EM> to attempt
to authenticate to the server using the supplied username.
An example might be:

<P>
<CENTER><SAMP>/user=katie</SAMP></CENTER>
<P>

</DD>

<DT>TLS</DT>
<DD>
Normally, when a new connection is made an attempt is made to 
negotiate a secure (encrypted) session using Transport Layer Security (TLS).
If that fails then a non-encrypted connection will be attempted instead.
This is a unary parameter indicating communication with the server must 
take place over a TLS connection. If the attempt to use TLS fails then
this parameter will cause the connection to fail instead of falling
back to an unsecure connection.

<P>
<CENTER><SAMP>/tls</SAMP></CENTER>
<P>

</DD>

<DT>SSL</DT>
<DD>
This is a unary parameter indicating communication with the server should 
take place over a Secure Socket Layer connection.  The server must support
this method, and be prepared to accept connections on the appropriate
port (993 by default).
<EM>Alpine</EM> must be linked with an SSL library for this option to be operational.

<P>
<CENTER><SAMP>/ssl</SAMP></CENTER>
<P>

</DD>

<DT>NoValidate-Cert</DT>
<DD>Do not validate certificates (for TLS or SSL connections) from the server.
This is needed if the server uses self-signed certificates or if <EM>Alpine</EM>
cannot validate the certificate for some other known reason.
<P>
</DD>

<DT>Anonymous</DT>
<DD>This is a unary parameter (that means it does not have a value)
indicating that the connection be logged in as
&quot;anonymous&quot; rather than a specific user.
Not all servers offer anonymous
access; those which do generally only offer read-only access to certain
&quot;public&quot; folders.

<P>
<CENTER><SAMP>/anonymous</SAMP></CENTER>
<P>

</DD>

<DT>Secure</DT>
<DD>This is a unary parameter indicating that the connection use the
most secure authentication method mutually supported by <EM>Alpine</EM> and the
server.
<EM>Alpine</EM> is capable of authenticating connections to 
the server using several methods.
By default, <EM>Alpine</EM> will attempt each
method until either a connection is established or the
list of methods is exhausted.
This parameter causes <EM>Alpine</EM> to instead fail 
the connection if the first (generally most &quot;secure&quot;) method fails.

<P>
<CENTER><SAMP>/secure</SAMP></CENTER>
<P>

</DD>

<DT>Submit</DT>
<DD>This is a unary parameter for use with the
&quot;SMTP-Server&quot; option.
It indicates that the connection should be made to the Submit server
(<A HREF="http://www.ietf.org/rfc/rfc2476.txt">RFC 3676</A>)
(port 587) instead of the SMTP port (25).
At the time this help was written the submit option was equivalent to
specifying port 587.

<P>
<CENTER><SAMP>/submit</SAMP></CENTER>
<P>
or
<P>
<CENTER><SAMP>host:587</SAMP></CENTER>
<P>

</DD>

<DT>Debug</DT>
<DD>This is a unary parameter indicating that the connection be established
in a verbose mode.  Basically, it causes <EM>Alpine</EM> to log the communication with
the server in <EM>Alpine</EM>'s debug file.
Normally, the alpine -d command-line flag would be used instead.
<P>
</DD>

<DT>NoRsh</DT>
<DD>By default, <EM>Alpine</EM> attempts to login using &quot;rsh&quot;,
the UNIX remote shell program.
Including &quot;NoRsh&quot; will cause connections to this server to skip
the &quot;rsh&quot; attempt.
This might be useful to avoid long timeouts caused by rsh firewalls, for
example.
<P>
</DD>

<DT>Service</DT>
<DD>This parameter requires an associated value.  The default value is
&quot;IMAP&quot; which indicates communication with the server based
on the IMAP4rev1 protocol (defined in RFC 3501 -- see 
<A HREF="http://www.imap.org/docs/rfc3501.html">http://www.imap.org/docs/rfc3501.html</A>).</DD>

Other service values include:
 <DL>
 <DT>NNTP</DT>
 <DD>This value indicates communication with the server takes place via
the Network News Transfer Protocol.  Use this to define a collection
of newsgroups on a remote news server.  So

<P>
<CENTER><SAMP>/service=NNTP</SAMP></CENTER>
<P>
or just
<P>
<CENTER><SAMP>/NNTP</SAMP></CENTER>
<P>

is the way to specify NNTP access.
<P>
 </DD>

 <DT>POP3</DT>
 <DD>This value indicates communication with the server takes place via the
Post Office Protocol 3 protocol.

<P>
<CENTER><SAMP>/service=POP3</SAMP></CENTER>
<P>
or just
<P>
<CENTER><SAMP>/POP3</SAMP></CENTER>
<P>

Note that there are several important issues
to consider when selecting this option:
<OL>
 <LI> POP3 provides access to only your INBOX.  In other words,
secondary folders such as your &quot;saved-messages&quot; are inaccessible.
 <LI> <EM>Alpine</EM>'s implementation of POP3 does not follow the traditional POP
model and will leave your mail on the server. Refer to the
<A HREF="#maildrop"><EM>Mail Drop</EM></A>
functionality for a possible way around this problem.
 <LI> See the discussion about new-mail checking in <A HREF="config.html#reopen-rule"><EM>Folder-Reopen-Rule</EM></A>.
</OL>
</DD>
</DL>
</DL>

<P>
Note that it is possible to include more than one parameter in a server
specification by concatenating the parameters. For example:

<P>
<CENTER><SAMP>foo.example.com:port/user=katie/novalidate-cert/debug</SAMP></CENTER>
<P>

<HR>

<H2><A NAME="folder-namespaces">Folder Namespaces</A></H2>

A <EM>Alpine</EM> folder name looks like

<P>
<CENTER><SAMP>[{&lt;remote-specification&gt;}][#&lt;namespace&gt;][&lt;namespace-specific-part&gt;]</SAMP></CENTER>
<P>

The local part of a folder name has an optional &quot;Namespace&quot; which
tells <EM>Alpine</EM> how to interpret the rest of the name.

<P> 
By default the folder name is interpreted as defining a section of your personal
folder area.  This area and how you specify it are defined by the
server, if one is specified, or, typically, the home
directory, if no server is defined.

<P>
If a namespace is specified, it begins with the
sharp, &quot;#&quot;, character followed by the name of the namespace
and then the namespace's path-element-delimiter.  Aside from the
path's format, namespaces can also imply access rights, content
policy, audience, location, and, occasionally, access methods.

<P>
Each server exports its own set (possibly of size one) of 
namespaces.  Hence, it's likely communication with your server's
administrator will be required for specific configurations.  Some of
the more common namespaces, however, include:

<DL>
<DT>#news.</DT>
<DD>This specifies a set of folders in the newsgroup namespace.  Newsgroup
names are hierarchically defined with each level delimited by a period.
<P>
<CENTER><SAMP>#news.comp.mail.pine</SAMP></CENTER>
<P>
</DD>
<DT>#public/</DT>
<DD>This specifies a folder area that the server may export to the general
public.
</DD>
<DT>#shared/</DT>
<DD>This specifies a folder area that the folder may export to groups
of users.
</DD>
<DT>#ftp/</DT>
<DD>This specifies a folder area that is the same as that it may have 
exported via the &quot;File Transfer Protocol&quot;.
</DD>
<DT>#mh/</DT>
<DD>This specifies the personal folder area associated with folders
and directories that were created using the MH message handling system.
</DD>
<DT>#move/</DT>
<DD>This namespace is interpreted locally by <EM>Alpine</EM>. It has an unusual interpretation and format.
<P>
<CENTER><SAMP>#move&lt;DELIM&gt;&lt;MailDropFolder&gt;&lt;DELIM&gt;&lt;DestinationFolder&gt;</SAMP></CENTER>
<P>
The <CODE>#move</CODE> namespace is followed by two folder names separated by a delimiter
character.
The delimiter character may be any character which does not appear in
the <CODE>MailDropFolder</CODE> name.
The meaning of <CODE>#move</CODE> is that mail will be copied from the <CODE>MailDropFolder</CODE> to
the <CODE>DestinationFolder</CODE> and then deleted (if possible) from the <CODE>MailDropFolder</CODE>.
Periodic checks at frequency
<A HREF="config.html#mail-check"><EM>Mail-Check-Interval</EM></A>, but with a minimum time between checks set by
<A HREF="config.html#maildrop-check-minimum"><EM>MailDrop-Check-Minimum</EM></A>,
are made for new mail arriving in the <CODE>MailDropFolder</CODE>.
An example which copies mail from a POP inbox to a local folder follows
<P>
<CENTER><SAMP>#move+{popserver.example.com/pop3/ssl}inbox+local folder</SAMP></CENTER>
<P>
To you it appears that mail is being delivered to the local folder when it
is copied from the <CODE>MailDropFolder</CODE>, and you read mail from the local folder.
<P>
Note that if the <CODE>DestinationFolder</CODE> does not exist then the messages are not
copied from the <CODE>MailDropFolder</CODE>.
A <CODE>#move</CODE> folder may only be used as an
<A HREF="config.html#enable-incoming-folders"><EM>Incoming folder</EM></A> or
an Inbox.
When you are in the FOLDER LIST of Incoming Message Folders (after turning
on the enable-incoming-folders option)
the Add command has a subcommand &quot;Use Mail Drop&quot;
which may be helpful for defining the folder in your <EM>Alpine</EM> configuration.
The same is true when you edit the
<A HREF="config.html#inbox-path"><EM>Inbox-Path</EM></A>
option in Setup/Config.
Each of these configuration methods will also create the <CODE>DestinationFolder</CODE>
if it doesn't already exist.
If you are having problems, make sure the <CODE>DestinationFolder</CODE> exists.
</DD>
</DL>
<P>

In addition, the server may support access to other user's folders,
provided you have suitable permissions.  Common methods use a prefix
of either &quot;~<VAR>user</VAR>/&quot;, or &quot;/<VAR>user</VAR>/&quot; to
indicate the root of the other user's folder area.
<P>

<HR>

<H2><A NAME="maildrop">What is a Mail Drop?</A></H2>

In some situaions it may make sense to have your mail delivered to one
folder (the Mail Drop) and then when you want to read mail that has been
delivered to the Mail Drop folder <EM>Alpine</EM> will move it to another
destination folder.
Often the Mail Drop will be a remote folder and messages will be moved from
there to a local destination folder.

<P>
One example where this might make sense is if the Mail Drop folder is accessible
only with the POP protocol.
You could designate your POP inbox as the Mail Drop folder and have <EM>Alpine</EM> move
mail from there to a local (on the same machine <EM>Alpine</EM> is running on)
destination folder, where you'll read it.

<P>
A Mail Drop may only be used as your Inbox or as an
<A HREF="config.html#enable-incoming-folders"><EM>Incoming folder</EM></A>.

<P>
There is no attempt to synchronize the contents of the destination folder
with the contents of the Mail Drop folder.
All that happens is that all of the messages in the Mail Drop folder are
copied to the destination folder and then they are deleted and expunged (if possible)
from the Mail Drop folder.
The next time a check for new mail is made, any messages in the Mail 
Drop folder are once again copied to the destination folder and deleted
and expunged from the Mail Drop folder.
(If the Mail Drop folder is a news group, then the messages can't be
expunged from the newsgroup. Instead, only Recent messages are copied from
the newsgroup to the destination folder.)

<P>
Configuration of a Mail Drop is a little different from configuration of
a folder which does not use a Mail Drop because you have to specify two
folder names instead of one.
The two folders may be any types of folders that <EM>Alpine</EM> can normally use.
They don't have to be a remote folder and a local folder, that is
simply the most common usage.
When you use a Mail Drop folder <EM>Alpine</EM> will periodically re-open the Mail
Drop to check for new mail.
The new-mail checks will happen at the frequency set with the
<A HREF="config.html#mail-check"><EM>Mail-Check-Interval</EM></A> option,
but with a minimum time
(<A HREF="config.html#maildrop-check-minimum"><EM>MailDrop-Check-Minimum</EM></A>)
between checks.
Because of this minimum you may notice that new mail does not
appear promptly when you expect it.
The reason for this is to protect the server from over-zealous opening and
closing of the Mail Drop folder.
If the user initiates the check by typing ^L (Ctrl-L) or the Next command when at
the end of the folder index, then the check will happen, regardless of how
long it has been since the previous check.
<P>
If there is new mail, that mail will be copied to the destination folder
and then will be deleted from the Mail Drop.
Note that using a Mail Drop with a local destination folder does not make
sense if you read mail from more than one machine, because the mail is
downloaded to the destination folder (which is accessible from only one
machine) and deleted from the Mail Drop.
<P>
The feature <A HREF="config.html#maildrops-preserve-state"><EM>Maildrops-Preserve-State</EM></A>
modifies the operation of Mail Drops.

<P>
The actual syntax used by <EM>Alpine</EM> for a folder that uses a Mail Drop is:

<P>
<CENTER><SAMP>#move&lt;DELIM&gt;&lt;MailDropFolder&gt;&lt;DELIM&gt;&lt;DestinationFolder&gt;</SAMP></CENTER>
<P>
The brackets are not literal.
<P>
<CENTER><SAMP>&lt;DELIM&gt;</SAMP></CENTER>
<P>
is a single character which does not appear in the <CODE>MailDropFolder</CODE> name.
If the name doesn't contain spaces then it can be a space character.
The two folder names are full technical
<A HREF="#server-name-syntax"><EM>folder names</EM></A>
as used by <EM>Alpine</EM>.
Here are a couple examples to give you an idea what is being talked about:

<P>
<CENTER><SAMP>#move&nbsp;{popserver.example.com/pop3}inbox&nbsp;localfolder</SAMP></CENTER>
<P>
<CENTER><SAMP>#move+{nntpserver.example.com/nntp}#news.comp.mail.pine+local&nbsp;folder</SAMP></CENTER>
<P>

A #move folder may only be used as an
<A HREF="config.html#enable-incoming-folders"><EM>Incoming folder</EM></A> or
an Inbox.
When you are in the FOLDER LIST of Incoming Message Folders (after turning
on the Enable-Incoming-Folders option)
the Add command has a subcommand &quot;Use Mail Drop&quot;
which may be helpful for defining the folder in your <EM>Alpine</EM> configuration.
The same is true when you edit the
<A HREF="config.html#inbox-path"><EM>Inbox-Path</EM></A>
option in Setup/Config.
</CODE>
if it doesn't already exist.
If you are having problems, make sure the <CODE>DestinationFolder</CODE> exists.
<P>

<HR>

<H2><A NAME="sorting">Sorting a Folder</A></H2>

The mail index may be sorted by arrival, date, subject,
from, size, score, to, or cc order.
Each sort order can also be reversed.  The <EM>$</EM> command will
prompt the user for the sort order.  The sort order can also be specified
on the command line with the <EM>-sort</EM> flag or (equivalently) with
the <A HREF="config.html#sort-key"><EM>sort-key</EM></A> variable in
the <EM>pinerc</EM> file.
When a user changes folders, the sort order will go back to the original
sort order. 
The command line (<EM>-sort</EM>) or configuration file sort specification
(<EM>sort-key</EM>) changes the original sort order.  <P>

When a folder is sorted and new mail arrives in the folder it will be
inserted in its properly sorted place.  This can be a little odd when the
folder is sorted by something like the subject.  It can also be a little
slow if you are viewing a large, sorted <EM>INBOX</EM>,
since the <EM>INBOX</EM> will have
to be re-sorted whenever new mail arrives.  <P>

The sorts are all independent of case and ignore leading or trailing white
space.  There are actually two forms of subject sort.  One called
<EM>Subject</EM> and the other called <EM>OrderedSubj</EM>.
They both ignore "Re:" at
the beginning and "(fwd)" at the end of the subjects.
<EM>Subject</EM> sorts all the subjects alphabetically.
<EM>OrderedSubj</EM> sorts by subjects alphabetically,
groups messages with the same subject (pseudo-threads),
then sorts the groups by the date of the first message of the group.
Sorting by <EM>Thread</EM> was added after <EM>OrderedSubj</EM>
and is usually a better method.
Thread sorting uses information in the message headers References,
Message-ID, and Subject.
It is possible the sort will be slightly slower with a Thread sort than
with an OrderedSubj sort.
The
sort by sender sorts by the user-id (part before the "@"), not the full name.
The arrival sort is no sort at all and the date
sort depends on the format of the date.
Some dates are in strange formats and are unparsable.
The time zone is also taken into account.  <P>

Sorting large mail folders can be very slow since it requires fetching all
the headers of the mail messages.
With UNIX <EM>Alpine</EM>, only the first sort is slow since <EM>Alpine</EM>
keeps a copy of all the headers.  One exception is sorting
in reverse arrival order.  This is fast because no headers have to be
examined.  <EM>Alpine</EM> will show progress as it is sorting.  <P>

<HR>

<H2><A NAME="alt-ed">Alternate Editor</A></H2>

In the <EM>Alpine</EM> composer you can use any text editor,
such as <EM>vi</EM> or <EM>emacs,</EM> for composing the message text.
The addresses and subject still must be edited using the standard
<EM>Alpine</EM> composer.
If you include the feature
<A HREF="config.html#enable-alt-ed"><EM>enable-alternate-editor-cmd</EM></A>
in your <EM>pinerc</EM> you can type <EM>^_</EM> while in the body of
the message in the composer and be prompted for the editor.
If you also set the <A HREF="config.html#editor"><EM>editor</EM></A> variable
in your <EM>pinerc</EM> then <EM>^_</EM> will invoke the configured
editor when you type it.  <P>

Turning on the feature
<A HREF="config.html#enable-alt-imp"><EM>enable-alternate-editor-implicitly</EM></A>
will automatically invoke the editor you have defined with the <EM>editor</EM>
variable whenever you enter the body of a message you are composing.  For
example, when you move out of the last header line and into the body of
the message, the alternate editor will be automatically invoked.  <P>

We know that many people would like to use the alternate editor to edit
the mail header as well.  We considered several designs for this and
didn't come up with one that we liked and that was easy to implement.  One
of the main problems is that you lose access to the address book.  <P>

<HR>

<H2><A NAME="signature">Signatures and Signature Placement</A></H2>

If the file <EM>~/.signature</EM> (UNIX) or
<EM>&lt;PINERC</EM>directory&gt;\PINE.SIG (PC) exists, it will be included
in all outgoing messages.  It is included before composition starts so
that the user has a chance to edit it out if he or she likes.  The file
name for the signature can be changed by setting the
<A HREF="config.html#sig-file"><EM>signature-file</EM></A>
variable in the <EM>pinerc</EM>.
If the feature <A HREF="config.html#sig-dash"><EM>enable-sigdashes</EM></A>
is turned on then the line consisting of the
three characters "<CODE>-- "</CODE> is prepended to the signature file.
When Replying or Forwarding a message different signatures my be automatically
included by configuring them in the
<A HREF="config.html#role-config"><EM>Roles</EM></A>
setup screen.
It's easy to include different signatures by hand, by having multiple
signature files (<EM>.sig1, .sig2, .sig3, etc</EM>) and choosing to
include (^R in the composer) the correct one for the message being sent. 
<P>

<EM>Alpine</EM>'s default behavior encourages
a user to put his or her contribution
before the inclusion of the original text of the message being forwarded
or replied to, This is contrary to some conventions, but makes the
conversation more readable when a long original message is included in a
reply for context.  The reader doesn't have to scroll through the original
text that he or she has probably already seen to find the new text.  If
the reader wishes to see the old message(s), the reader can scroll further
into the message.  Users who prefer to add their input at the end of a
message should set
the <A HREF="config.html#sig-at-bot"><EM>signature-at-bottom</EM></A> feature.
The signature will then be appended to the end of
the message after any included text.
This feature applies when <EM>Reply</EM>ing, not when <EM>Forward</EM>ing.  <P>

<HR>

<H2><A NAME="feature-list">Feature List Variable</A></H2>

<EM>Alpine</EM> used to have <EM>feature levels</EM> for
users with different amounts of experience.
We found that this was too restrictive.  <EM>Alpine</EM> now has a
<A HREF="config.html#feat-list"><EM>feature-list</EM></A> instead.
Each user may pick and choose which
features they would like enabled (simple to do in the <EM>Setup/Config</EM>
screen).  There is a short description of each in <A HREF="config.html#features-conf"><EM>Configuration Features</EM></A>. There is also a short on-line
help explaining the effect of each of
the features in the <EM>Setup/Config</EM> screen.
When the cursor is highlighting
a feature, the <EM>?</EM> command will show the help text for that feature. 
Features don't have values, they are just turned on or off.  They are all
off by default.  <P>

The <EM>feature-list</EM> variable is different from all other
configuration variables in that its value is additive.  That is, the
system-wide configuration file can have some features turned on by
default.  The user can select other features in their personal
configuration file and those features will be <STRONG>added</STRONG> to
the set of features turned on in the system-wide configuration file. 
(With all other configuration variables, the user's values
<STRONG>replace</STRONG> the system-wide values.) Likewise, additional
features may be set on the command-line with the argument
"-feature-list=".  These will be added to the others.  <P>

The treatment of <EM>feature-list</EM> in the system-wide <EM>fixed</EM>
configuration file is also different from other variables.  The system
management can fix the value of individual features by placing them in the
fixed configuration file.  Users will not be able to alter those features,
but will still be able to set the other non-restricted features the way
they like.  <P>

Because <EM>feature-list</EM> is additive, there is a way to turn features
off as well as on.  Prepending the prefix "no-" to any feature sets it to
off.  This is useful for over-riding the system-wide default in the
personal configuration file or for over-riding the system-wide default or
the personal configuration value on the command line.  For example, if the
system-wide default configuration has the <EM>quit-without-confirm</EM>
feature set, the user can over-ride that (and turn it off) by including
<EM>no-quit-without-confirm</EM> in the personal configuration file or by
giving the command line argument
<EM>-feature-list=no-quit-without-confirm.</EM> More features (options)
will no doubt continue to be added.  <P>

<HR>

<H2><A NAME="config-inheritance">Configuration Inheritance</A></H2>

We start with an explanation of how configuration works in hopes of making
it easier to describe how inheritance works.
<P>
<EM>Alpine</EM> uses a hierarchy of configuration values from different locations.
There are five ways in which each configuration option (configuration
variable) can be set.
In increasing order of precedence they are:
<P>
<OL>
<LI> the system-wide configuration file.

<LI> the personal configuration file

<LI> the personal exceptions file

<LI> a command line argument

<LI> the system-wide <EM>fixed</EM> configuration file (Unix <EM>Alpine</EM> only)
</OL>
<P>
The fixed configuration file is normally
<CODE>/usr/local/lib/pine.conf.fixed</CODE>.
<P>
The system-wide configuration file is normally
<CODE>/usr/local/lib/pine.conf</CODE> for Unix <EM>Alpine</EM> and is normally not
set for <EM>PC-Alpine</EM>.
For <EM>PC-Alpine</EM>, if the environment variable <EM>$PINECONF</EM> is set, that
is used for the system-wide configuration.
This location can be set or changed on the command line with the -P flag.
The system-wide configuration file can be either a local file or a
remote configuration folder.
<P>
For Unix <EM>Alpine</EM>, the personal configuration file is normally the file
<CODE>.pinerc</CODE> in the user's home directory.
This can be changed with the -p command line flag.
For <EM>PC-Alpine</EM>, the personal configuration file is in
<CODE>$PINERC</CODE> or <CODE>&lt;PineRC registry value&gt;</CODE> or 
<CODE>${HOME}&#92;ALPINE&#92;PINERC</CODE> or
<CODE>&lt;ALPINE.EXE </CODE>dir<CODE>&gt;&#92;PINERC</CODE>.
This can be changed with the -p command line flag.
If -p or <CODE>$PINERC</CODE> is used, the configuration data may be in
a local file or a remote config folder.
<P>
For Unix <EM>Alpine</EM>, the personal exceptions configuration file is
specified with the &quot;-x exceptions_config&quot; command line argument.
&quot;Exceptions_config&quot; may be either a local file or a remote
configuration folder.
If there is no &quot;-x&quot; command line option,
<EM>Alpine</EM> will look for the file &quot;<CODE>.pinercex</CODE>&quot;
in the same local directory that the regular config file is located in.
If the regular config file is remote then Unix <EM>Alpine</EM> looks in the home
directory for &quot;<CODE>.pinercex</CODE>&quot;.
<P>
For <EM>PC-Alpine</EM>, the personal exceptions configuration file is
specified with the &quot;-x exceptions_config&quot; command line argument.
If there is no &quot;-x&quot; command line argument the environment
variable <CODE>$PINERCEX</CODE> may be set to the name of the
&quot;exceptions_config&quot; instead.
&quot;Exceptions_config&quot; may be either a local file or a remote
configuration folder.
If there is no &quot;-x&quot; command line option and <CODE>$PINERCEX</CODE>
is not set,
<EM>PC-Alpine</EM> will look for the file &quot;<CODE>PINERCEX</CODE>&quot;
in the same local directory that the regular config file is located in.
If the regular config file is remote then <EM>PC-Alpine</EM> looks in the
local directory specified by the &quot;-aux local_directory&quot; command
line argument, or the directory <CODE>${HOME}&#92;ALPINE</CODE>, or
in <CODE>&lt;ALPINE.EXE </CODE>directory<CODE>&gt;</CODE> for a file named
&quot;<CODE>PINERCEX</CODE>&quot;.
<P>
To reiterate, the value of a configuration option is taken from the
last location in the list above in which it is set.
Or, thinking about it slightly differently, a default value for an option
is established in the system-wide configuration file (or in the source
code if there is no value in the system-wide file).
That default remains in effect until and unless it is overridden by a value in a
location further down the list, in which case a new &quot;default&quot;
value is established.
As we continue down the list of locations we either retain the
value at each step or establish a new value.
The value that is still set after going through the whole list of
configuration locations is the one that is used.
<P>
So, for example, if an option is set in the system-wide configuration
file and in the personal configuration file, but is not set in the
exceptions, on the command line, or in the fixed file; then the value
from the personal configuration file is the one that is used.
Or, if it is set in the system-wide config, in the personal config, not
in the exceptions, but is set on the command line; then the value
on the command line is used.
<P>
Finally we get to inheritance.
For configuration options which are lists, like &quot;smtp-server&quot; or
&quot;incoming-folders&quot;,
the inheritance mechanism makes it possible to <EM>combine</EM>
the values from different locations instead of <EM>replacing</EM> the value.
This is true of all configuration lists other than the &quot;feature-list&quot;,
for which you may already set whatever you want at
any configuration location (by using the &quot;no-&quot; prefix if
necessary).
<P>
To use inheritance, set the first item in a configuration list to the
token &quot;INHERIT&quot;.
If the first item is &quot;INHERIT&quot;,
then instead of replacing the default value established so far, the rest of
the list is appended to the default value established so far and that is
the new value.
<P>
Here is an example which may make it clearer. Suppose we have:
<P>
<PRE>
 System-wide config :   smtp-server = smtp1.corp.com, smtp2.corp.com
 Personal config    :   smtp-server = INHERIT, mysmtp.home
 Exceptions config  :   smtp-server = &lt;No Value Set&gt;
 Command line       :   smtp-server = &lt;No Value Set&gt;
 Fixed config       :   smtp-server = &lt;No Value Set&gt;
</PRE>
<P>

This would result in an effective smtp-server option of
<P>
<PRE>
 smtp-server = smtp1.corp.com, smtp2.corp.com, mysmtp.home
</PRE>
<P>
The &quot;INHERIT&quot; token can be used in any of the configuration files
and the effect cascades.
For example, if we change the above example to:
<P>
<PRE>
 System-wide config :   smtp-server = smtp1.corp.com, smtp2.corp.com
 Personal config    :   smtp-server = INHERIT, mysmtp.home
 Exceptions config  :   smtp-server = INHERIT, yoursmtp.org
 Command line       :   smtp-server = &lt;No Value Set&gt;
 Fixed config       :   smtp-server = &lt;No Value Set&gt;
</PRE>
<P>

This would result in:
<P>
<PRE>
 smtp-server = smtp1.corp.com, smtp2.corp.com, mysmtp.home, yoursmtp.org
</PRE>
<P>
Unset variables are skipped over (the default value is carried forward) so
that, for example:
<P>
<PRE>
 System-wide config :   smtp-server = smtp1.corp.com, smtp2.corp.com
 Personal config    :   smtp-server = &lt;No Value Set&gt;
 Exceptions config  :   smtp-server = INHERIT, yoursmtp.org
 Command line       :   smtp-server = &lt;No Value Set&gt;
 Fixed config       :   smtp-server = &lt;No Value Set&gt;
</PRE>
<P>

produces:
<P>
<PRE>
 smtp-server = smtp1.corp.com, smtp2.corp.com, yoursmtp.org
</PRE>
<P>

If any later configuration location has a value set (for a particular list
option) which does <EM>not</EM> begin with &quot;INHERIT&quot;,
then that value replaces whatever value has been defined up to that point.
In other words, that cancels out any previous inheritance.
<P>
<PRE>
 System-wide config :   smtp-server = smtp1.corp.com, smtp2.corp.com
 Personal config    :   smtp-server = INHERIT, mysmtp.org
 Exceptions config  :   smtp-server = yoursmtp.org
 Command line       :   smtp-server = &lt;No Value Set&gt;
 Fixed config       :   smtp-server = &lt;No Value Set&gt;
</PRE>
<P>

results in:
<P>
<PRE>
 smtp-server = yoursmtp.org
</PRE>
<P>

For some configuration options, like &quot;viewer-hdr-colors&quot; or
&quot;patterns-roles&quot;, it is
difficult to insert the value &quot;INHERIT&quot; into the list of values
for the option using the normal Setup tools.
In other words, the color setting screen (for example) does not
provide a way to input the text &quot;INHERIT&quot; as the first
item in the viewer-hdr-colors option.
The way to do this is to either edit the pinerc file directly and manually
insert it, or turn on the &quot;expose-hidden-config&quot; feature and insert it
using the Setup/Config screen.
<P>

<HR>

<H2><A NAME="env-variables">Using Environment Variables</A></H2>

The values of <EM>Alpine</EM> configuration options may include environment variables
which are replaced by the value of the variable at the time <EM>Alpine</EM> is run
(and also at the time the config option is changed).
The syntax to use environment variables is a subset of the common Unix
shell dollar-syntax.
For example, if

<P><CENTER><SAMP>$VAR</SAMP></CENTER><P>

appears in the value of a <EM>Alpine</EM> configuration option it is looked up in the
environent (using getenv(&quot;VAR&quot;)) and its
looked-up value replaces the <SAMP>$VAR</SAMP> part of the option value.
To include a literal dollar sign you may precede the dollar sign with another
dollar sign.
In other words, if the text

<P><CENTER><SAMP>$$text</SAMP></CENTER><P>

is the value of a configuration option, it will be expanded to

<P><CENTER><SAMP>$text</SAMP></CENTER><P>

and no environment lookup will be done.
For Unix <EM>Alpine</EM> it will also work to use a backslash character to
escape the special meaning of the dollar sign, but $$ is preferable since
it works for both <EM>PC-Alpine</EM> and Unix <EM>Alpine</EM>, allowing the configuration option
to be in a shared configuration file.
<P>

This all sounds more complicated than it actually is.
An example may make it clearer.
Unfortunately, the way in which environment variables are set is OS-dependent 
and command shell-dependent.
In some Unix command shells you may use

<P><CENTER><SAMP>PERSNAME="Fred Flintstone"</SAMP></CENTER><P>
   <CENTER><SAMP>export PERSNAME</SAMP></CENTER><P>

Now, if you use <EM>Alpine</EM>'s Setup/Config screen to set

<P><CENTER><SAMP>personal-name=$PERSNAME</SAMP></CENTER><P>

the <SAMP>$PERSNAME</SAMP> would be replaced by <SAMP>Fred Flintstone</SAMP>
so that this would be equivalent to

<P><CENTER><SAMP>personal-name=Fred Flintstone</SAMP></CENTER><P>

Note, environment variable substitution happens after configuration
options which are lists are split into the separate elements of the list,
so a single environment variable can't contain a list of values.

<P>
The environment variable doesn't have to be the only thing
after the equal sign.
However, if the name of the variable is not at the end of the line or
followed by a space (so that you can tell where the variable name ends),
it must be enclosed in curly braces like

<P><CENTER><SAMP>${VAR}</SAMP></CENTER><P>

It is always ok to use the braces even if you don't need to.
<P>
It is also possible to set a default value for an environment variable.
This default value will be used if the environment variable is not
set (that is, if getenv(&quot;VAR&quot;) returns NULL).
The syntax used to set a default value is

<P><CENTER><SAMP>${VAR:-default value}</SAMP></CENTER><P>

If the config file contains

<P><CENTER><SAMP>personal-name=${VAR:-Fred Flintstone}</SAMP></CENTER><P>

then when <EM>Alpine</EM> is run <SAMP>VAR</SAMP> will be looked up in the environment.
If <SAMP>VAR</SAMP> is found then <SAMP>personal-name</SAMP> will have
the value that <SAMP>VAR</SAMP> was set to, otherwise,
<SAMP>personal-name</SAMP> will be set to <SAMP>Fred Flintstone</SAMP>,
the default value.

<P>
An example where an environment variable might be useful is the
variable <SAMP>inbox-path</SAMP> in the global configuration file.
Suppose most users used the server

<P><CENTER><SAMP>imapserver.example.com</SAMP></CENTER><P>

but that there were some exceptions who used

<P><CENTER><SAMP>altimapserver.example.com</SAMP></CENTER><P>

In this case, the system manager might include the following line in
the systemwide default <EM>Alpine</EM> configuration file

<P><CENTER><SAMP>inbox-path=${IMAPSERVER:-imapserver.example.com}</SAMP></CENTER><P>

For the exceptional users adding

<P><CENTER><SAMP>IMAPSERVER=altimapserver.example.com</SAMP></CENTER><P>

to their environment should work.
<P>
Another example might be the case where a user has to use a different
SMTP server from work and from home.
The setup might be something as simple as

<P><CENTER><SAMP>smtp-server=$SMTP</SAMP></CENTER><P>

or perhaps a default value could be given.
Note that, as mentioned above, the variable <SAMP>SMTP</SAMP> cannot contain
a list of SMTP servers.
<P>

<HR>

<H2><A NAME="smtp-server">SMTP Servers</A></H2>

It is sometimes desirable to set <CODE>smtp-server=localhost</CODE>
instead of setting
<A HREF="config.html#sendmail-path"><EM>sendmail-path</EM></A>
to overcome the inability to
negotiate ESMTP options when <EM>sendmail</EM> is invoked with the
<EM>-t</EM> option.  Sendmail can also be subject to unacceptable delays
due to slow DNS lookups and other problems. <P>

It is sometimes desirable to configure an SMTP server on a port other
than the default port 25.  This may be used to provide an alternate
service that is optimized for a particular environment or provides
different features from the port 25 server.  An example would be a program
that negotiates ESMTP options and queues a message, but does not attempt
to deliver messages.  This would avoid delays frequently encountered when
invoking <EM>sendmail</EM> directly. <P>

A typical configuration would consist of

<UL>

<LI> A program that implements the SMTP or ESMTP protocol via stdio.

<LI> An entry in <CODE>/etc/services</CODE> for the alternate service.

<LI> An entry in <CODE>/etc/inetd.conf</CODE> for the alternate service.

<LI> An entry in <CODE>/usr/local/lib/pine.conf</CODE>,
<CODE>/usr/local/lib/pine.conf.fixed</CODE> or <CODE>~/.pinerc</CODE>. 

</UL>

<HR>

<H2><A NAME="mime.types">MIME.Types file</A></H2>

<EM>Alpine</EM>'s MIME-TYPE support is based on code contributed by Hans Drexler
&LT;drexler@mpi.nl&GT;.  <EM>Alpine</EM> assigns MIME Content-Types according
to file name extensions found in the system-wide files
<CODE>/usr/local/lib/mime.types</CODE> and <CODE>/etc/mime.types</CODE>,
and a user specific <CODE>~/.mime.types</CODE> file.  <P>

In Windows,
<EM>Alpine</EM> looks in the same directory as the PINERC file and
the same dir as ALPINE.EXE.  This is similar to the UNIX situation with
personal config info coming before potentially shared config data.  An
alternate search path can be specified by setting the
<A HREF="config.html#mimetype-search-path"><EM>mimetype-search-path</EM></A>
variable in the user or system-wide
configuration or by setting the <CODE>MIMETYPES</CODE> environment
variable. <P>

These files specify file extensions that will be connected to a mime type. 
Lines beginning with a '<CODE>#</CODE>' character are treated as comments
and ignored.  All other lines are treated as a mime type definition.  The
first word is a <EM>type/subtype</EM> specification.  All following words
are file <EM>extensions</EM> belonging to that type/subtype. Words are
separated by whitespace characters.  If a file extension occurs more than
once, then the first definition determines the file type and subtype.
A couple sample lines from a mime.types file follow: <P>

<PRE>
image/gif         gif
text/html         html htm
video/mpeg        mpeg mpg mpe<BR>
</PRE>

<HR>

<H2><A NAME="color-config-notes">Color Details</A></H2>

UNIX <EM>Alpine</EM> may display color if the terminal or terminal emulator you
are using is capable of displaying colors.
If the terminal supports ANSI color escape sequences you will be able to
turn color on using the <A HREF="config.html#color-style">color-style</A>
option and setting it to the value <EM>force-ansi-8color</EM> or
<EM>force-ansi-16color</EM>.
If instead you'd like <EM>Alpine</EM> to automatically detect whether or not
you are on a color terminal, set <EM>color-style</EM> to <EM>use-termdef</EM>
<EM>and</EM> configure the termcap entry to describe your terminal's
color capabilities.
<P>

If the <EM>color-style</EM> option is set to <EM>use-termdef</EM>,
<EM>Alpine</EM> looks in
the terminal capabilities database, TERMINFO or TERMCAP, depending on
how <EM>Alpine</EM> was compiled, to decide whether or not your terminal is
capable of color.
For TERMINFO compiled <EM>Alpine</EM>s, the capabilities that are used for
color are
&quot;colors&quot;, &quot;setaf&quot;, &quot;setab&quot;,
&quot;op&quot;, and &quot;bce&quot;.
If you have a terminal with color capabilities described by
the &quot;scp&quot; capability, <EM>Alpine</EM> does not support it.
The capabilities
&quot;setf&quot; and &quot;setb&quot; may be used instead of
&quot;setaf&quot; and &quot;setab&quot;.
The capability &quot;bce&quot; is optional and is used as an optimization,
the other capabilities are required.
For TERMCAP compiled <EM>Alpine</EM>s, the capabilities that are used for
color are
&quot;Co&quot;, &quot;AF&quot;, &quot;AB&quot;, &quot;op&quot;,
and &quot;ut&quot;.
The capabilities
&quot;Sf&quot; and &quot;Sb&quot; may be used instead of
&quot;AF&quot; and &quot;AB&quot;, though this isn't a useful feature.
<P>

Here are some short descriptions of the capabilities listed
above.
The TERMINFO name is listed, followed by the TERMCAP name in parentheses.
<DL COMPACT>

<DT> <EM>colors</EM> (<EM>Co</EM>)

<DD> The number of different colors.
<P>

<DT> <EM>setaf</EM> (<EM>AF</EM>)

<DD> Set ANSI foreground color.
<P>

<DT> <EM>setab</EM> (<EM>AB</EM>)

<DD> Set ANSI background color.
<P>

<DT> <EM>setf</EM> (<EM>Sf</EM>)

<DD> Set foreground color. Alternate form of <EM>setaf</EM>.
<P>

<DT> <EM>setb</EM> (<EM>Sb</EM>)

<DD> Set background color. Alternate form of <EM>setab</EM>.
<P>

<DT> <EM>op</EM> (<EM>op</EM>)

<DD> Set default pair to its original value.
<P>

<DT> <EM>bce</EM> (<EM>ut</EM>)

<DD> Screen is erased with current background color instead
of default background.
<P>

<P>
</DL>
<P>
A standard ANSI terminal which supports color will have
a TERMINFO entry which contains:
<PRE>
  colors#8
  setaf=\E[3%p1%dm
  setab=\E[4%p1%dm
  op=\E[39;49m
  bce
</PRE>
<P>
or the TERMCAP equivalent:
<PRE>
  Co#8
  AF=\E[3%dm
  AB=\E[4%dm
  op=\E[39;49m
  ut
</PRE>
<P>

If there are eight colors, the program uses colors 0, 1, ..., 7.
For an ANSI terminal, the foreground color is set by sending the escape
sequence &quot;Escape LeftBracket 3 color_number m&quot; to the terminal.
The background color is set by sending the sequence
&quot;Escape LeftBracket 4 color_number m&quot;.
ANSI colors zero through seven are defined to be &quot;black&quot;,
&quot;red&quot;, &quot;green&quot;, &quot;yellow&quot;, &quot;blue&quot;,
&quot;magenta&quot;, &quot;cyan&quot;, and &quot;white&quot;.
Some terminal emulators will swap blue and red and swap yellow and cyan.
The capabilities &quot;setf&quot; and &quot;setb&quot; are usually designed
for those terminals so that they will flip the color numbers 1 and 4 and
the numbers 3 and 6 to compensate for this.
<EM>Alpine</EM> will use the ANSI versions of the capabilities if they exist,
and will use the non-ANSI versions (setf and setb) if the ANSI versions
don't exist.
Here's a version which does the flipping.
This can only be used with TERMINFO <EM>Alpine</EM>s, because of the arithmetic,
which is not supported by TERMCAP.
<PRE>
  colors#8
  setf=\E[3%?%p1%{1}%=%t4%e%p1%{3}%=%t6%e%p1%{4}%=%t1%e%p1%{6}%=%t3%e%p1%d%;m
  setb=\E[4%?%p1%{1}%=%t4%e%p1%{3}%=%t6%e%p1%{4}%=%t1%e%p1%{6}%=%t3%e%p1%d%;m
  op=\E[39;49m
  bce
</PRE>
<P>

Some terminal emulators are capable of displaying eight more colors when
the foreground colors 30-37 are replaced with 90-97 and the background
colors 40-47 are replaced with 100-107.
These terminals require a fancy termcap entry which can take foreground
colors 0, 1, ..., 15 and map that into 30, 31, ..., 37, 90, 91, ..., 97,
and similarly for the background colors.
Here is a terminfo entry which will do just that:
<PRE>
  colors#16
  setaf=%p1%{8}%/%{6}%*%{3}%+\E[%d%p1%{8}%m%dm
  setab=%p1%{8}%/%{6}%*%{4}%+\E[%d%p1%{8}%m%dm
  op=\E[39;49m
  bce
</PRE>
and here is the termcap equivalent:
<PRE>
  Co#16
  AF=\E[%i%i%>\001\034%>\045\064%dm
  AB=\E[%i%i%>\001\046%>\057\064%dm
  op=\E[39;49m
  ut
</PRE>
<P>
This is a terminfo entry for 16 colors that also does the color flipping:
<PRE>
  colors#16
  setf=%p1%{8}%/%{6}%*%{3}%+\E[%d%p1%{8}%m%Pa%?%ga%{1}%=%t4%e%ga%{3}%=%t6%e%ga%{4}%=%t1%e%ga%{6}%=%t3%e%ga%d%;m
  setb=%p1%{8}%/%{6}%*%{4}%+\E[%d%p1%{8}%m%Pa%?%ga%{1}%=%t4%e%ga%{3}%=%t6%e%ga%{4}%=%t1%e%ga%{6}%=%t3%e%ga%d%;m
  op=\E[39;49m
  bce
</PRE>
<P>

If you are always using the same display it probably won't matter to you
if the color pairs red/blue and cyan/yellow are flipped, since you'll
always be seeing them flipped.
You will get different defaults than on a display with them not flipped,
but that's about all.
If you are trying to use the same pinerc file from displays with different
color characteristics, or from <EM>Alpine</EM> and <EM>PC-Alpine</EM>, you will
have to be more careful.
The colors numbered 0 through 7 may be used portably between different
systems if you are careful to make them correspond to the ANSI order mentioned
above.
You can check this by looking at a color configuration screen for one of the
colors.
The first eight colors should be in the order above.
If they aren't, you could fix that by modifying your termcap entry on
the UNIX system.
This is not possible if your system uses TERMCAP instead of TERMINFO.

<HR>

<H2><A NAME="smime-general">S/MIME Overview</A></H2>

UNIX <EM>Alpine</EM> only.
<P>
S/MIME is a standard for the public key encryption and signing of email.
UNIX <EM>Alpine</EM> contains a basic implementation of S/MIME based on
the <A HREF="http://www.openssl.org/">OpenSSL</A> libraries.
<P>
Some limitations:
<UL>
   <LI> There is no <EM>PC-Alpine</EM> implementation.
   <LI> There is no provision for checking for CRLs
	(Certificate Revocation Lists) in <EM>Alpine</EM>.
   <LI> This built-in S/MIME implementation is not compatible with and does not help with PGP.
   <LI> There is no mechanism available for feeding either an entire incoming
	or an entire outgoing message to an external
	filter and using that external filter to do S/MIME or PGP processing.
   <LI> Because the implementation currently uses OpenSSL, there is only a very
	limited integration with the Mac OS Keychain (the storing and access of
	public certificates).
   <LI> There is no way to view or manipulate the lists of certificates from
	within <EM>Alpine</EM>.
</UL>
<P>
The S/MIME configuration screen is reached by going to the Main Menu and typing
the &quot;S&nbsp;Setup&quot; command followed by &quot;M&nbsp;S/MIME&quot;.
<P>

<H3>S/MIME BASICS</H3>

In order to digitally sign messages you send you must have a public/private key-pair.
This may be obtained from a public Certificate Authority (CA) such as Thawte, Verisign, Comodo,
or GoDaddy; or from a smaller CA such as a university which provides certificates for its
users or a company which provides certificates for its workers.
These certificates are bound to an email address, so the identity being verified is the
email address not a person's name.
<P>
Mail is signed by using the sender's private key, which only the owner of the private key
has access to.
The signature is verified using the signer's public key, which anyone can
have access to.
With <EM>Alpine</EM>, the first time you receive a signed message the public key of the
sender will be stored for future use.

<P>
Mail is encrypted using the recipient's public key and decrypted by
the recipient with their private key.

<P>
You need a key of your own in order to sign outgoing messages and to have others
encrypt messages sent to you.
You do not need a key of your own to verify signed messages sent by others or to
encrypt messages sent to others.

<H3>ALPINE S/MIME CERTIFICATE STORAGE</H3>

By default UNIX <EM>Alpine</EM> stores the certificates it uses in a directory in your
home directory.
The directory name is
<P>
<CENTER><SAMP>.alpine-smime</SAMP></CENTER>
<P>
Within that directory are three subdirectories.
Each of the three subdirectories contains files with PEM-encoded contents,
the default format for OpenSSL.
The &quot;<SAMP>public</SAMP>&quot; directory contains public certificates.
The files within that directory have names that are email addresses with the
suffix &quot;<SAMP>.crt</SAMP>&quot; appended.
An example filename is
<P>
<CENTER><SAMP>user@example.com.crt</SAMP></CENTER>
<P>
The &quot;<SAMP>private</SAMP>&quot; directory contains private keys, probably just one for
your private key.
These are also email addresses but with the suffix &quot;<SAMP>.key</SAMP>&quot; instead.
The third directory is &quot;<SAMP>ca</SAMP>&quot; and it contains certificates for any Certificate
Authorities that you want to trust but that aren't contained in the set of system CAs.
Those files may have arbitrary names as long as they end with the
suffix &quot;<SAMP>.crt</SAMP>&quot;.

<H3>HOW TO SIGN AND ENCRYPT</H3>

If you have a certificate you may sign outgoing messages.
After typing the Ctrl-X command to send a message you will see the prompt
<P>
<CENTER><SAMP>Send message?</SAMP></CENTER>
<P>
Available subcommands include &quot;G&nbsp;Sign&quot; and &quot;E&nbsp;Encrypt&quot;.
Typing the &quot;G&quot; command will change the prompt to
<P>
<CENTER><SAMP>Send message (Signed)?</SAMP></CENTER>
<P>
Typing the &quot;E&quot; command will change the prompt to
<P>
<CENTER><SAMP>Send message (Encrypted)?</SAMP></CENTER>
<P>
You may even type both to get
<P>
<CENTER><SAMP>Send message (Encrypted, Signed)?</SAMP></CENTER>
<P>

<H3>HOW TO READ SIGNED OR ENCRYPTED MESSAGES</H3>

The reading of a signed message should not require any special action on
your part.
There should be an editorial addition at the start of the message which
says either
<P>
<CENTER><SAMP>This message was cryptographically signed.</SAMP></CENTER>
<P>
or
<P>
<CENTER><SAMP>This message was cryptographically signed but the signature could not be verified.</SAMP></CENTER>
<P>
If an encrypted message is sent to you the encrypted text will not
be shown.
You will have to type the &quot;Ctrl-D&nbsp;Decrypt&quot; command (from the screen where
you are viewing the message) and supply your passphrase when asked.
<P>
For a signed or encrypted message there is also a &quot;Ctrl-E&nbsp;Security&quot; command
which gives you some information about the certificate used to sign or encrypt the message.

<H3>MISCELLANEOUS</H3>

You may have access to a private certificate in the PKCS12 format,
which would sometimes be in a file with a &quot;.p12&quot; suffix.
The UNIX shell command
<P>
<CENTER><SAMP>openssl pkcs12 -in file.p12 -out file.pem</SAMP></CENTER>
<P>
may work to convert that from the PKCS12 format to the PEM format.
Then that file could be placed in the &quot;<SAMP>private</SAMP>&quot;
directory with a filename of your email address followed by the
suffix &quot;<SAMP>.key</SAMP>&quot;.

<HR>

<H2><A NAME="pc-notes">Additional Notes on PC-Alpine</A></H2>

Below are a few odds and ends worth mentioning about <EM>PC-Alpine</EM>.  They have
to do with DOS-specific behavior that is either necessary or useful (and
sometimes both!).  <P>

As <EM>PC-Alpine</EM> runs in an environment with limited access control, accounting
or auditing, an additional line is automatically inserted into the header
of mail messages generated by <EM>PC-Alpine</EM>: 

<PRE>
	X-Sender: &lt;userid&gt;@&lt;imap.host&gt;<BR>
</PRE>
<P>

By popular demand of system administrators, <EM>PC-Alpine</EM> has been modified to
prevent sending messages until the user has successfully logged into a
remote mail server.  Even though <EM>PC-Alpine</EM> cannot prevent users from
changing the apparent identity of the sender of a message, the IMAP server
login name and host name included in the <EM>X-Sender</EM> line
provide some level of traceability by the recipient.
However, this should not be considered a
rigorous form of authentication.  It is extremely lightweight, and is not
a replacement for true authentication.  <P>

Hand in hand with authentication and accounting is user information. 
Since <EM>PC-Alpine</EM> has no user database to consult for <EM>user-id</EM>,
<EM>personal-name</EM>, etc., necessary information must be provided by
the user/installer before <EM>PC-Alpine</EM> can properly construct the "From"
address required for outbound messages.  <EM>PC-Alpine</EM> will, by default, prompt
for the requisite pieces as they are needed.  This information corresponds
to the <EM>PINERC</EM> variables
<A HREF="config.html#user-id"><EM>user-id</EM></A>,
<A HREF="config.html#personal-name"><EM>personal-name</EM></A>,
<A HREF="config.html#user-domain"><EM>user-domain</EM></A>,
and <A HREF="config.html#smtp-server"><EM>smtp-server</EM></A>.  <P>

The user is then asked whether or not this information should
automatically be saved to the <EM>PINERC</EM>.  This is useful behavior in
general, but can lead to problems in a lab or other shared environment. 
Hence, these prompts and automatic saving of configuration can be turned
off on an entry by entry basis by setting any of the above values in the
<EM>PINERC</EM> to the null string (i.e., a pair of double quotes).  This
means that the user will be prompted for the information once during each
<EM>Alpine</EM> session, and no opportunity to save them in the <EM>PINERC</EM> will
be offered.  <P>

Another feature of DOS is the lack of standard scratch area for temporary
files.  During the course of a session, <EM>PC-Alpine</EM> may require numerous
temporary files (large message texts, various caches, etc.).  Where to
create them can be a problem, particularly when running under certain
network operating systems.  <EM>PC-Alpine</EM> observes the
<EM>TMPDIR</EM>, <EM>TMP</EM>, and
<EM>TEMP</EM> environment variables, and creates temporary files in the
directory specified by either. In their absence, <EM>PC-Alpine</EM> creates these
files in the root of the current working drive.
Some temporary files have to be created in the same directory as the file
they are a temporary copy of. For example, a pinerc file or a address book
file.
<P>
 
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