# Notes on Configuration and Preferences

## Pine in Function Key Mode

The standard Pine 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.

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

One of the results of using Pine 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.

## Domain Settings

Pine 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 Pine to check if an address is that of the current Pine user.

Pine determines the domain name according to whichever of these it finds. The list here is in decreasing order of precedence.

1. Value of the variable user-domain in the system fixed configuration file
2. Value of the variable user-domain in the personal configuration file
3. Value of the variable user-domain in the system-wide configuration file
4. Value from an external database (DNS, `/etc/hosts`, NIS) as modified by a system fixed configuration file if use-only-domain-name set to yes
5. Value from an external database (DNS, `/etc/hosts`, NIS) as modified by a personal configuration file if use-only-domain-name set to yes
6. Value from an external database (DNS, `/etc/hosts`, NIS) as modified by a system configuration file if use-only-domain-name set to yes
7. Unmodified value (host name) from an external database

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

## Syntax for Collections

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 Pine, access to these archives is just as simple as access to folders on Pine's local disk.

"Collection" is the word we use in Pine 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 Pine will adjust its menus and prompts to help navigate them.

The way collections are defined in Pine is with the folder-collections variable in the Pine configuration file. Folder-collections takes a list of one or more collections, each (optionally) preceded by a user-defined logical name (label). Once collections are defined, Pine adjusts its menus and behavior to allow choosing files by their simple name within the collection.

Consider the following:

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

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). Pine 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.

The collection specifier can be thought of as an extended IMAP format (see the Remote Folders 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.

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:

    	M-Mail		C:MAIL/[m*]

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.

From within Pine, the "Folder List" display will be adjusted to allow browsing of the folders in any defined collection. Even more, you'll notice in the Goto and Save 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.

The first collection specified in the folder-collections 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 Save a message, the default collection for saves will be used. Also, if the default-fcc is a relative file name, then it is relative to the default collection for saves. (See also saved-msg-name-rule.

The notion of collections encompasses both email folders and news reading. The variable news-collections uses nearly the same format as folder-collections. 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.

An example pinerc entry might be:

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

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

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:

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

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 Pine configuration file you get simple management of multiple folders in diverse locations.

As of Pine 4.00, collection setup is handled by the Setup/collectionList screen instead of requiring hand editing of the configuration file.

## Syntax for Remote Folders

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 IMAP server and is in a form compatible with that server (i.e., path delimiters and naming syntax relative to that server).

Typically, a folder name without any path description is understood to reside in the user's "home directory" (i.e., in some way the user's personal, writable file area), as are incomplete path designations. However, the IMAP specification does not require that unqualified folder names live in one's home directory, so some IMAP servers may require fully qualified names. An example of a remote folder specification would be,

    	{host.dept.washington.edu}mail/saved-messages

This example simply specifies a folder named ``saved-messages'' on the imap server ``host.dept.washington.edu'', in the ``mail'' subdirectory of the user's home directory. Easy isn't it?

To confuse things a bit, qualifiers are permitted within the brackets following the host name. These qualifiers consist of a slash ('/') character followed by a keyword or keyword and value, and have the effect of modifying how the connection is made to the host specified. An example of such a specification might be,

    	{news.u.washington.edu/nntp}#news.comp.mail.mime

This specifies an altogether different access method: access via the Network News Transport Protocol (NNTP).

Some other possible qualifiers are `/user=username`, which says to login as user username; `/secure`, which says to use the most secure authentication method supported by Pine and the server and fail to connect if that authentication fails; `/imap`; `/pop3`; `/debug`; `/ssl`, which says to use a secure SSL connection; `/novalidate-cert`, which tells Pine to not attempt to validate certificates from SSL server; and `/anonymous`.

There is also an optional `:portnum` following the hostname. This would specify a non-standard port number to connect to.

## Sorting a Folder

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 $ command will prompt the user for the sort order. The sort order can also be specified on the command line with the -sort flag or (equivalently) with the sort-key variable in the pinerc file. When a user changes folders, the sort order will go back to the original sort order. The command line (-sort) or configuration file sort specification (sort-key) changes the original sort order.

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 INBOX, since the INBOX will have to be re-sorted whenever new mail arrives.

The sorts are all independent of case and ignore leading or trailing white space. There are actually two forms of subject sort. One called Subject and the other called OrderedSubj. They both ignore "Re:" at the beginning and "(fwd)" at the end of the subjects. Subject sorts all the subjects alphabetically. OrderedSubj 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 Thread was added after OrderedSubj 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.

Sorting large mail folders can be very slow since it requires fetching all the headers of the mail messages. With UNIX Pine, only the first sort is slow since Pine 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. Pine will show progress as it is sorting.

## Alternate Editor

In the Pine composer you can use any text editor, such as vi or emacs, for composing the message text. The addresses and subject still must be edited using the standard Pine composer. If you include the feature enable-alternate-editor-cmd in your pinerc you can type ^_ while in the body of the message in the composer and be prompted for the editor. If you also set the editor variable in your pinerc then ^_ will invoke the configured editor when you type it.

Turning on the feature enable-alternate-editor-implicitly will automatically invoke the editor you have defined with the editor 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.

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.

## Signatures and Signature Placement

If the file ~/.signature (UNIX) or <PINERCdirectory>\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 signature-file variable in the pinerc. If the feature enable-sigdashes is turned on then the line consisting of the three characters "`-- "` is prepended to the signature file. When Replying or Forwarding a message different signatures my be automatically included by configuring them in the Roles setup screen. It's easy to include different signatures by hand, by having multiple signature files (.sig1, .sig2, .sig3, etc) and choosing to include (^R in the composer) the correct one for the message being sent.

Pine'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 signature-at-bottom feature. The signature will then be appended to the end of the message after any included text. This feature applies when Replying, not when Forwarding.

## Feature List Variable

Pine used to have feature levels for users with different amounts of experience. We found that this was too restrictive. Pine now has a feature-list instead. Each user may pick and choose which features they would like enabled (simple to do in the Setup/Config screen). There is a short description of each in Configuration Features. There is also a short on-line help explaining the effect of each of the features in the Setup/Config screen. When the cursor is highlighting a feature, the ? 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.

The feature-list 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 added to the set of features turned on in the system-wide configuration file. (With all other configuration variables, the user's values replace 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.

The treatment of feature-list in the system-wide fixed 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.

Because feature-list 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 quit-without-confirm feature set, the user can over-ride that (and turn it off) by including no-quit-without-confirm in the personal configuration file or by giving the command line argument -feature-list=no-quit-without-confirm. More features (options) will no doubt continue to be added.

## Configuration Inheritance

We start with an explanation of how configuration works in hopes of making it easier to describe how inheritance works.

Pine 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:

1. the system-wide configuration file.
2. the personal configuration file
3. the personal exceptions file
4. a command line argument
5. the system-wide fixed configuration file (Unix Pine only)

The fixed configuration file is normally `/usr/local/etc/pine.conf.fixed`.

The system-wide configuration file is normally `/usr/local/etc/pine.conf` for Unix Pine and is normally not set for PC-Pine. For PC-Pine, if the environment variable $PINECONF 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.

For Unix Pine, the personal configuration file is normally the file `.pinerc` in the user's home directory. This can be changed with the -p command line flag. For PC-Pine, the personal configuration file is in `$PINERC` or `<PineRC registry value>` or `$HOME\PINE\PINERC` or `<PINE.EXE` dir`>\PINERC`. This can be changed with the -p command line flag. If -p or `$PINERC` is used, the configuration data may be in a local file or a remote config folder.

For Unix Pine, the personal exceptions configuration file is specified with the "-x exceptions_config" command line argument. "Exceptions_config" may be either a local file or a remote configuration folder. If there is no "-x" command line option, Pine will look for the file "`.pinercex`" in the same local directory that the regular config file is located in. If the regular config file is remote then Unix Pine looks in the home directory for "`.pinercex`".

For PC-Pine, the personal exceptions configuration file is specified with the "-x exceptions_config" command line argument. If there is no "-x" command line argument the environment variable `$PINERCEX` may be set to the name of the "exceptions_config" instead. "Exceptions_config" may be either a local file or a remote configuration folder. If there is no "-x" command line option and `$PINERCEX` is not set, PC-Pine will look for the file "`PINERCEX`" in the same local directory that the regular config file is located in. If the regular config file is remote then PC-Pine looks in the local directory specified by the "-aux local_directory" command line argument, or the directory `$HOME\PINE`, or in `<PINE.EXE` directory`>` for a file named "`PINERCEX`".

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 "default" 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.

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.

Finally we get to inheritance. For configuration options which are lists, like "smtp-server" or "incoming-folders", the inheritance mechanism makes it possible to combine the values from different locations instead of replacing the value. This is true of all configuration lists other than the "feature-list", for which you may already set whatever you want at any configuration location (by using the "no-" prefix if necessary).

To use inheritance, set the first item in a configuration list to the token "INHERIT". If the first item is "INHERIT", 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.

Here is an example which may make it clearer. Suppose we have:

     System-wide config :   smtp-server = smtp1.corp.com, smtp2.corp.com
     Personal config    :   smtp-server = INHERIT, mysmtp.home
     Exceptions config  :   smtp-server = <No Value Set>
     Command line       :   smtp-server = <No Value Set>
     Fixed config       :   smtp-server = <No Value Set>

This would result in an effective smtp-server option of

     smtp-server = smtp1.corp.com, smtp2.corp.com, mysmtp.home

The "INHERIT" token can be used in any of the configuration files and the effect cascades. For example, if we change the above example to:

     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 = <No Value Set>
     Fixed config       :   smtp-server = <No Value Set>

This would result in:

     smtp-server = smtp1.corp.com, smtp2.corp.com, mysmtp.home, yoursmtp.org

Unset variables are skipped over (the default value is carried forward) so that, for example:

     System-wide config :   smtp-server = smtp1.corp.com, smtp2.corp.com
     Personal config    :   smtp-server = <No Value Set>
     Exceptions config  :   smtp-server = INHERIT, yoursmtp.org
     Command line       :   smtp-server = <No Value Set>
     Fixed config       :   smtp-server = <No Value Set>

produces:

     smtp-server = smtp1.corp.com, smtp2.corp.com, yoursmtp.org

If any later configuration location has a value set (for a particular list option) which does not begin with "INHERIT", then that value replaces whatever value has been defined up to that point. In other words, that cancels out any previous inheritance.

     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 = <No Value Set>
     Fixed config       :   smtp-server = <No Value Set>

results in:

     smtp-server = yoursmtp.org

For some configuration options, like "viewer-hdr-colors" or "patterns-roles", it is difficult to insert the value "INHERIT" 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 "INHERIT" 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 "expose-hidden-config" feature and insert it using the Setup/Config screen.

## SMTP Servers

It is sometimes desirable to set `smtp-server=localhost` instead of setting sendmail-path to overcome the inability to negotiate ESMTP options when sendmail is invoked with the -t option. Sendmail can also be subject to unacceptable delays due to slow DNS lookups and other problems.

It is sometimes desireable 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 sendmail directly.

A typical configuration would consist of

- A program that implements the SMTP or ESMTP protocol via stdio.
- An entry in `/etc/services` for the alternate service.
- An entry in `/etc/inetd.conf` for the alternate service.
- An entry in `/usr/local/etc/pine.conf`, `/usr/local/etc/pine.conf.fixed` or `~/.pinerc`.

## MIME.Types file

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

In DOS and OS/2, Pine looks in the same directory as the PINERC file and the same dir as PINE.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 mimetype-search-path variable in the user or system-wide configuration or by setting the `MIMETYPES` environment variable.

These files specify file extensions that will be connected to a mime type. Lines beginning with a '`#`' character are treated as comments and ignored. All other lines are treated as a mime type definition. The first word is a type/subtype specification. All following words are file extensions 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:

    image/gif         gif
    text/html         html htm
    video/mpeg        mpeg mpg mpe

## Color Details

UNIX Pine 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 color-style option and setting it to the value force-ansi-8color or force-ansi-16color. If instead you'd like Pine to automatically detect whether or not you are on a color terminal, set color-style to use-termdef and configure the termcap entry to describe your terminal's color capabilities.

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

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

colors (Co)
  The number of different colors.

setaf (AF)
  Set ANSI foreground color.

setab (AB)
  Set ANSI background color.

setf (Sf)
  Set foreground color. Alternate form of setaf.

setb (Sb)
  Set background color. Alternate form of setab.

op (op)
  Set default pair to its original value.

bce (ut)
  Screen is erased with current background color instead of default background.

A standard ANSI terminal which supports color will have a TERMINFO entry which contains:

      colors#8
      setaf=\E[3%p1%dm
      setab=\E[4%p1%dm
      op=\E[39;49m
      bce

or the TERMCAP equivalent:

      Co#8
      AF=\E[3%dm
      AB=\E[4%dm
      op=\E[39;49m
      ut

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 "Escape LeftBracket 3 color_number m" to the terminal. The background color is set by sending the sequence "Escape LeftBracket 4 color_number m". ANSI colors zero through seven are defined to be "black", "red", "green", "yellow", "blue", "magenta", "cyan", and "white". Some terminal emulators will swap blue and red and swap yellow and cyan. The capabilities "setf" and "setb" 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. Pine 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 Pines, because of the arithmetic, which is not supported by TERMCAP.

      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

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:

      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

and here is the termcap equivalent:

      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

This is a terminfo entry for 16 colors that also does the color flipping:

      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

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 Pine and PC-Pine, 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.

## Additional Notes on PC-Pine

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

As PC-Pine 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 PC-Pine:

    	X-Sender: <userid>@<imap.host>

By popular demand of system administrators, PC-Pine has been modified to prevent sending messages until the user has successfully logged into a remote mail server. Even though PC-Pine 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 X-Sender 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.

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

The user is then asked whether or not this information should automatically be saved to the PINERC. 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 PINERC 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 Pine session, and no opportunity to save them in the PINERC will be offered.

Along similar lines, a feature allowing automatic login to the imap-server containing the user's INBOX has also been requested. This feature is not enabled by default, but requires the existence of the file named PINE.PWD in the same directory as the PINERC. Even with the existence of this file, the user must still acknowledge a prompt before the password is saved to the file. If PC-Pine is configured to access several different IMAP servers, each password entered will be kept (associated with the corresponding host name) in memory during the current session, and optionally, in the PINE.PWD file for use in subsequent sessions.

WARNING! Use this feature with caution! It effectively makes the user's mail no more secure than the physical security of the machine running PC-Pine. What's more, while the password is cloaked by a mild (some might say, feeble) encryption scheme, it is nonetheless sitting in a file on the PC's disk and subject to cracking by anyone with access to it. BEWARE!

Another feature of DOS is the lack of standard scratch area for temporary files. During the course of a session, PC-Pine 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. PC-Pine observes the TMPDIR, TMP, and TEMP environment variables, and creates temporary files in the directory specified by either. In their absence, PC-Pine 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.