Filtering Mail
[previous]
[next]
[table of contents] [index]
One of the strong points of exmh is its support for mail
filtering systems that file messages into different folders as
they are delivered.
Filters look for patterns in the mail headers.
For example, you can put all mail from your boss into one folder
and all mail from a mailing list or digest into another folder.
The standard MH mail filtering system is described
in the Chapter Processing New Mail Automatically.
You can also use the procmail system or even write your own.
exmh supports filters that use the
rcvstore program
to file messages into different folders as they arrive.
It visually highlights the folders that have new mail.
This depends on the definition of the Unseen-Sequence: profile
entry and the support of this sequence by the mail
filtering system.
Both the slocal
and procmail filtering systems will
add new messages to the unseen sequence if that sequence is defined in
your profile.
The inc program also adds messages to the unseen sequence.
So, even if you don't filter mail, exmh will highlight
new messages in inbox.
CAUTION:
If you use the .maildelivery file to filter messages,
you should always have a default action in the file that refiles the
messages into your inbox (or some catch-all folder).
If you do not supply a default, you get the default action
for your system, which might not be what you want.
If neither you nor the system provides a default action,
mail that does not match a filter
may be discarded!
The filtering support affects the way you incorporate mail from
your system mailbox.
exmh supports four different styles: inbox,
multidrop, presort, and none.
Use the Incorporate Mail preference section to choose one.
You may also want to enable periodic Inc under the
Background Processing preference section.
- inbox
-
Inc moves new messages into your inbox folder.
This is the default.
No filtering is done.
exmh highlights the inbox folder label when
new mail is incorporated.
Unread messages are
highlighted.
- none
-
If you use a filtering system to deliver messages into various
folders, then you don't need Inc in the user interface.
Selecting "none" eliminates the Inc button and
disables the internal Inc procedure.
A background "flist" task (Section Background Processing)
is a nice complement to this setting;
it shows you which folders are getting mail.
- presort
-
Inc moves new messages directly into various folders.
This is similar to what you may be doing already with
a filtering system.
This built-in exmh features eliminates the need for
a filtering system.
Presort incorporates mail from your system mailbox
into a temporary folder (MyIncTmp).
Then, it runs the MH filtering hook slocal
on each message.
In this mode, it is expected that the filtering action is to put
the message into a folder.
You do this by specifying an action that pipes the message
into the MH rcvstore program.
- multidrop
-
This assumes that you use MH maildelivery facilities (see
mhook) to put new messages into a set of dropboxes
(inbox-like files) that correspond to different folders.
A dropbox can also be a POP host.
In this case,
Inc moves messages from the dropboxes to folders
named by your ~/.xmhcheck file
(see the Example .xmhcheck file below).
Your ~/.maildelivery file contains the filtering specifications
that MH uses.
In practice, I use a small subset of the maildelivery features.
See the MH
mhook(1)
manual page (called
slocal(1)
on some systems) for details.
The general format of each entry is:
field value action result command
The field is the header field (line) you are matching -- or
the default keyword.
The very last entry labeled default is the most important
entry in the whole file.
Without a good default, the maildelivery system seems happy to
discard arriving messages that don't match other entries.
value is a string to match in the specified field.
It is not case-sensitive.
The action is one of the following.
The > (or "file") action concatenates the message onto the named file.
The | (or "pipe") action runs the message through the following command.
The + action refiles the message into the named folder.
The + is supported only if you patch slocal with the
patch that comes with exmh.
You can also get the refile behavior by piping the message into the
rcvstore MH library program.
The result is one of the following.
The A result says to consider the message delivered if it matches,
no matter if it has matched something else.
The ? result says to consider the message delivered if it matches
and not to try to match a message that is already considered delivered.
Thus, the order of the ? entries is significant.
The R result says to perform the action and never consider the
message delivered.
A .maildelivery file that goes with multidrop incing
contains
a number of entries that concatenate matching messages onto a file:
Example: .maildelivery file for multidrop inc
#field value action result command
#----- ----- ------ ------ -------
default - pipe R "popup -m 'New mail from $(reply-to)' -dl 1&"
Subject TAX > ? Mail/in.tax
Subject mxedit > ? Mail/in.mxedit
X-Filters-Matched mxedit > ? Mail/in.mxedit
to welch > ? Mail/in.personal
X-Filters-Matched ouster > ? Mail/in.tcl
To tclusers > ? Mail/in.tcl
cc tclusers > ? Mail/in.tcl
subject " tcl" > ? Mail/in.tcl
default - > ? Mail/in.inbox
If you use multidrop-style inc,
then you also need a .xmhcheck file
that specifies the correspondence between inbox files and folders.
If your site uses POP to access mail stored at remote hosts,
you can specify the host and username used to access
the remote mail.
Note that it is not strictly necessary to fetch
remote mail from different mail hosts into different folders;
you could fetch everything into inbox.
Here is an example:
Example: .xmhcheck file
personal Mail/in.personal
mxedit Mail/in.mxedit
tcl Mail/in.tcl
tax Mail/in.tax
inbox Mail/in.inbox
work mailhost.my.com myname
school mailhost.my.edu myname
You can also pipe messages into programs.
The MH rcvstore program is very useful.
It puts
an arriving message directly into a folder.
Unfortunately, rcvstore is in the
MH library directory.
That directory probably isn't in your search path.
Type in its complete pathname, or make a symbolic link
to the program and specify that in your pipeline.
The Example below shows the presort inc style.
Example: .maildelivery file for presort inc
subject "Sun-Spots Digest" | A ".mhto +sunspots -create"
to "sunflash" | A ".mhto +sunspots -create"
to "ravenscroft" | A ".mhto +dl/ravens -create"
to "TodayatXerox" | A ".mhto +today -create"
to "Modula3" | A ".mhto +m3 -create"
to "nceg" | A ".mhto +nceg -create"
to "WRC_Systems_Reports" | A ".mhto +tech -create"
to "pencomputing" | A ".mhto +pencompute -create"
default - | A ".mhto"
The .mhto program is merely a symbolic link (in your home directory
or another directory in your UNIX command search path)
to the MH rcvstore program (in the MH library directory).
The | says to pipe the message into the program.
The A result says to perform the action upon a match,
regardless of whether the message is considered delivered already.
On a match, consider the message delivered.
So, the difference between ? and A actions is that
multiple A entries might match on a given message, whereas
only one ? will.
Finally, exmh comes with a patch to the MH slocal program that
simplifies the process of piping a message into rcvstore.
It adds the + command. (I switched from A to ? for no particular reason.) For example:
Example: .maildelivery file for exmh-modified slocal
subject "Sun-Spots Digest" + ? sunspots
to "sunflash" + ? sunspots
to "ravenscroft" + ? dl/ravens
to "TodayatXerox" + ? today
to "Modula3" + ? m3
to "nceg" + ? nceg
to "WRC_Systems_Reports" + ? tech
to "pencomputing" + ? pencompute
default - + ? inbox
Again, remember that the default entry is very important!
|
