Overview: Sending MH Messages
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Each of the four MH programs that are used to compose a mail
message -- comp, repl, forw, and dist -- does some
things differently from the others.
For example, comp composes an original message, and forw forwards
existing ones.
repl can build its header automatically; you fill in headers for the
other three programs.
But the programs have a lot in common.
They all build a draft file in the same way, they all use prompter
(unless you choose another editor), and they all have a
What now? prompt.
This section is about those similarities.
To create a MIME message, you put special directives in the draft file.
Next, you give the draft to mhn; it formats the draft for MIME.
Most MIME messages are created with comp, but you can use forw
and repl too.
too.
Each of the four mail-creating programs has its own template draft file.
This file helps to form the draft message.
For instance, the default template file for comp
is named components.
The components file looks like this (unless someone on your
system has changed it):
To:
cc:
Subject:
-------
The row of dashes separates the message header from the body.
It's automatically replaced with an empty line when you send the message.
When you start comp, it copies components into the draft file.
The template file for repl is different -- it's not just copied.
Instead, the file, called replcomps, has MH formatting commands that
automatically fill in the header of the draft file for you.
forw and dist have their own twists, too.
The Figure below
shows how they all work.
If you want to change the order of the fields -- or add new ones -- in all the
messages that you send with an MH command, read the Section
Draft Message Template Files.
Figure: Sending a message. Step 1: Making draft from template
After the comp, repl, forw, and dist commands
make the draft file in their own ways, they all start a program
called whatnow.
The first thing whatnow does is start an editor.
The default editor is named prompter.
(The Section Changing Default Editors
explains more.)
prompter reads and edits the draft file, line by line.
First it handles the header (up to the line of dashes).
Next it handles the body.
The next Figure has an example.
Figure: Sending a message. Steps 2-4: Draft message, before and after prompter edits it
The Header
If the draft file has any empty header fields such as:
To:
prompter prompts you to fill them in.
By now you know that if you leave the field empty, prompter just
deletes that field from the draft.
Normally, after you fill in a field and press
RETURN,
prompter reads the next header field and shows it on your screen.
But if you type a backslash (\) at the end of a line just before
you press
RETURN,
prompter will keep collecting the same header field.
That lets you put long lists of addresses in, say, the cc: field.
% comp
To: uunet!somewhere!somebody
cc: jjensen@bigcorp.se, lvalois@somecorp.fr, myboss,\
phogan@auscorp.au
Subject:
You must start each of the continuation lines with a space or tab.
The sidebar When is a Backslash Not a Backslash?
has more about this often-used character.
To add or change the fields in a header, you can either edit the header
after
prompter is finished or make
your own private template files.
The Body
After the row of dashes in the draft file, prompter starts collecting
the body of the message from your terminal exactly as you type it.
Remember that prompter doesn't wrap lines; you should press
RETURN
at the end of every line.
It reads until you press
CTRL-D
at the start of a line.
(prompter reads what you type until it gets the end-of-input
character.
There's a chance that your account is set up to use something besides
CTRL-D
as end-of-input.)
MH 6.7 added a new -doteof switch for prompter.
If you set this switch (usually in your MH profile), then
prompter will accept a single dot (.) at the start of a line,
by itself, as the end of the draft message.
Next, if there was text in the message body when you started prompter
(you're forwarding a message, re-editing an existing draft, and so on),
prompter will scroll that text across your screen.
With big messages or slow terminals, this can take time.
If you don't want to see the included text, add the -rapid switch
to the prompter: entry in your MH profile.
(If you have -rapid set and you want to see the included text, just
type list at a What now? prompt.)
If your message had included text, there's one more pair of switches
you might want to know about:
-prepend and -noprepend.
Because most users like to "set and forget" about these, the explanation is
in the Section How the Draft Message is Built.
After you end the body of the message by typing (usually)
CTRL-D,
prompter quits and the draft message is handled by the
whatnow program.
It gives you a list of choices for your draft message.
To see the list, just press
RETURN
at the
What now? prompt.
That list covers only the most common things you can do at the
What now? prompt.
Most commands accept other switches to change their operation.
For instance, send -width 60 tells send
to fold header address fields that are more than 60 characters wide.
Or list afile will display the file named afile in your
current directory and then give you another What now? prompt.
For a quick list of switches, you can add -help to most commands,
as in the following example:
What now? send -help
syntax: send [file] [switches]
switches are:
...
What now?
Here's more information about each choice, with abbreviations in parentheses:
list (or the letter l)
Shows the draft message you just typed.
To do this, it calls the lproc program
listed in your MH profile -- by default, it's a program like
more(1)
or
less(1).
On most systems this shows the draft screen by screen -- to see the next
screen, press either the space bar or
RETURN
(depending on the program that list uses).
If your system is set up for MIME and you've created the MIME message
with edit mhn (see below), list may be configured in two ways:
-
If your lproc is a pager like more, then list will show
the encoded draft (with base64 text like +/ho,
quoted-printable characters like =A1, and so on).
-
Or, if your lproc is the MH show command, you'll hear the
sounds, see characters like ñ,
and so on. In this case, if you want to see the encoded draft, use a pager program like
more(1)
as an "editor":
type edit more.
(See below.)
When list is done, you'll get another
What now? prompt.
display (or d)
Works only with the repl and dist
programs.
It shows the message that you're replying to or distributing;
otherwise
display is just like
list.
edit (or e)
Uses the default editor (usually prompter,
or whatever editor you were using) to edit the draft.
When you leave the editor, you'll get another What now? prompt.
You can set a different default editor in your MH profile.
See the Section Editor-next.
(Another kind of default editor for MIME messages is the
automhnproc.)
edit editor (or e editor)
Edits the draft with the editor named editor (example:
edit vi).
When you leave the editor, you'll get another What now? prompt.
Then you can use yet another editor program or any of the other whatnow
commands.
After you enter the directives for a MIME message, you'll type
edit mhn to create the draft.
The Section Sending MIME Mail has an example.
The "editor" program doesn't really have to be an editor.
Any UNIX program that accepts a filename argument will work -- including
shell programs that you write.
For example, you can type
edit append filename
to append a file to your draft.
The command edit original runs a shell script named
original
to undo the effects of mhn formatting.
As long as the "editor" program doesn't modify the draft file, you can use
the edit command to do anything else you can do with a standard UNIX
program and a file.
Here are some "editors" you can use at the What now? prompt:
- edit spell
-
Runs the draft through the UNIX speller and shows you the misspelled words.
- edit head
-
Runs
head(1)
to read the first ten lines of your draft.
That usually shows the header pretty well.
- edit wc
-
Counts the number of lines, words, and characters in your draft (including
the header).
- edit lpr
-
(or edit lp, depending on your print command)
sends the draft to the printer.
quit (or q)
Leaves the draft message file where it is and takes you back to the
shell prompt (%).
You use this if you want to do something else and come back to your draft
message later.
To find out how, see the Section
Working with Draft Messages.
quit -delete (or q -d)
Deletes the draft message you've been
working on and takes you to a shell prompt.
Use this if you decide not to send the message.
The dash (-) in -delete isn't required, but that's undocumented
and may be changed.
The Section Deleted Draft Messages
explains what happens
when the draft is deleted -- and how to change your mind after you delete
a draft.
refile +folder (or r +folder)
Moves the draft message into the folder you name.
The draft won't be sent.
You'll get another shell prompt.
See the Section Folders.
refile -link +folder (or r -l +folder)
Links a copy of the draft message into the folder you name,
but leaves the draft there to be sent.
Now, no matter what command you type at the next
What now? prompt, a copy of the draft will stay in the
folder named folder.
You'll get another shell prompt.
The Section Moving and Linking Messages: refile
has more information.
whom (or w)
Lists the addresses that the message will go to.
This is useful with aliases (Section MH Aliases).
When whom is done, you'll get another What now? prompt.
whom -check (or w -check)
Lists the addresses that the message will go to
and tells you if the address looks "deliverable."
(On some versions of MH, whom -check just prints the cryptic error
whom: Only one message at a time!...
even when there is only one message.
Plain whom, without the -check switch, doesn't have the problem.)
Unfortunately, this doesn't mean that the mail will really get there.
Depending on how the message is sent, an Address OK
message from whom means something like "the remote hostname looks
okay" or "the network is available."
Many electronic mail systems still can't tell you whether your mail addresses
are correct -- you have to wait to see if the message is returned to you.
This may or may not be the situation on your host.
But whom -check will try to tell you if addresses are
"deliverable" and show you something about them.
Although you can use whom from a shell prompt (like %),
you'll usually use it at the What now? prompt.
Here's an example, with the middle left out:
% comp
To: gurus
...
What now? whom -check
danro... deliverable
rada... deliverable
rbwilbur@mysun.xyz.edu... deliverable
"| /usr/local/lib/mh/slocal -user ahof"... deliverable
Here, whom shows that the gurus mail alias has four members.
The first two of them look like addresses on the local computer.
The third has mail forwarded to another computer,
and the fourth has mail forwarded to a mail-handling program
(slocal -- see the Chapter
Processing New Mail Automatically.
My computer uses the sendmail transfer agent, so whom calls
sendmail to check the addresses.
If your computer uses a different transfer agent, your whom output
may look different.
Again, whom can't guarantee that your message will get through.
But you can be fairly sure that if whom tells you there's a problem,
you should check into it.
Be sure your addresses are written correctly -- if that doesn't help, ask an
expert who knows your computer's transfer agent.
send (or s)
Sends the message as shown in the next
Figure Sending a message. Steps 5-6: After composing the draft.
Depending on how your system's transfer agent is set up and where your
message is going, the message may not be delivered for a few minutes, or
even a couple of days.
All "send" really means is "deliver the message to the transfer agent."
The rest is up to that transfer agent.
(send actually gives the message to the MH program called post,
which in turn gives it to the transfer agent.)
Figure: Sending a message. Steps 5-6: After composing the draft
If the message was sent (to the transfer agent!) successfully, you'll get
another shell prompt.
If there were problems, you may see the error on your screen or
you may get a mail message that explains what went wrong.
Again, it all depends on your system's setup. If you send MIME messages, an
automhnproc
program can run automatically,
when you type send, to process the message with mhn.
You can add a sendproc processing program that does any handling you
want before the message is given to MH for delivery.
One handy sendproc shell program is
mysend.
MH versions with MIME support have a -split switch that
automatically splits the message into pieces.
This helps to be sure that the message gets through gateways and systems
with message size limits.
If your message is just plain text, the recipient shouldn't need a MIME
mail reader to reassemble the split message:
removing all but the first header, then concatenating the message bodies,
will give back the original message.
See the Section Partial Messages.
send -watch -verbose (or s -wa -v)
Gives you an idea of what's happening as MH delivers your message to the
transfer agent.
(The undocumented -snoop switch on some versions of MH gives more
information.)
How much you see depends on several things.
If your system is set up to do it, you'll see the SMTP transaction
that delivers your message across the network to the remote machine.
push (or p)
Runs send with its -push
switch, which sends your message "in the background."
In other words, you'll get another shell prompt right away.
The only exception is when you have an
automhnproc:
mhn will be run before you get another shell prompt;
that can take time, prompt you for input, or even give another
What now? prompt if there are errors to fix.
(The -split switch for the send command also works with
push.
You won't see the progress messages as the parts are sent.)
Using push has good and bad points.
You can do something else while MH sends the message; that can be good,
especially on a slow system or when it takes time to deliver the message.
But the draft file will stay there until it's been processed.
That can be bad:
-
If you're using the -annotate switch of
forw, dist, or repl,
the message won't be annotated until it's sent.
That means you'd better not refile the message until it's
been annotated!
(On systems with long delays, try refiling the message before you
reply and annotate it.
A script named replf is handy for that.
It's in
this book's online archive -- and also
in the mtrenv directory of the MH distribution.)
To see if the message has been annotated, scan the original message
and look for the dash (-) before the date.
Here's the scan line for an example
annotated message.
(If your scan can't find the message, try again.
The message "disappears" for a moment as it's annotated.)
-
If you aren't using a
draft folder and you try to
start a new draft message before the first one has been sent in the
background, here's what will happen:
Draft '/yourMHdir/draft' exists; disposition? quit
You should quit and wait for the draft to be sent.
While you're waiting, think about setting up a draft folder.
It avoids this problem.
The Figure
Sending a message. Steps 5-6: After composing the draft
is a diagram that shows what send (and send -push) do with the
finished draft.
The Section Automatic Signature on End of Messages
shows how to edit your draft template files to add a
standard signature to the end of many (but not all) of your messages.
Another Section has the append shell script, an editor you
run from the What Now? prompt to add files to the end of
a draft before you send it.
This section shows a third way: a shell script that edits your draft
message when you execute:
What now? send
(It also works when you use push.)
The script is written to append a copy of the file .signature
from your home directory, with a line of two dashes before it.
That's easy to change by editing the script.
By default, the script does not add your signature unless you type:
What now? send -signature
(Abbreviate that -sig if you'd like.)
You can change a shell variable to make the opposite the default:
a signature unless you type -nosig.
No matter what, the script won't add a signature if the draft you're
composing is from the
dist command.
Any other arguments you type at What now? are passed
to the standard MH send command.
mysend runs it after editing the draft.
Of course, mysend can do more to a draft than add a signature.
Whatever you do, remember that the script processes all
of your mail; make sure the script is reliable and does what you want.
A
test mail setup is a good
place for debugging a script this important.
To install the script, add this entry to your MH profile:
sendproc: /xxx/yyy/mysend
where /xxx/yyy is the location of mysend
on the filesystem.
NOTE:
This script doesn't work with the dist command on some versions of
MH (Version 6.7.2, at least).
Those versions won't
tell the post command to allow a message to be redistributed.
The bug only happens when you add your own sendproc program;
it had nothing to do with this mysend script.
As a result, errors like these occur during the dist command:
What now? send
post: illegal header line -- Resent-To:
post: illegal header line -- Resent-cc:
If you use dist and your MH version has that bug, you should
also use the mydist script in Section Explanation of mysend.
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