1) Use editline [optional]:
Most of this code was borrowed from src/usr.bin/ftp. It does the
appropriate editing, history, and completion for all mail commands
(from cmdtab[]) and also does editing on header strings ('~h' inside
the mail editor).
2) '-B' flag:
This will suppress the "To:" line passed to sendmail. In most
configurations it will lead to sendmail adding "To: undisclosed
recipients;". Currently, AFAIK mail requires at least one exposed
recipient address.
3) Comments in rcfile:
Currently, comments in .mailrc are only supported if the first
(non-white) character on a line is '#' followed by white space,
i.e., '#' is a 'nop' command. This (trivial) patch allows the more
normal/expected use of '#' as a comment character. It does not
respect quoting, so that might be an objection which I should fix.
4) Sendmail option editing:
This adds the sendmail option string to the strings editable by the
'~h' command within the mail editor. Currently, you can only set
this string from the command-line, which is particularly annoying
when replying to mail.
5) Reply from:
When replying to a message, grab the "To:" address from the message
and, if there is only one such address and it does not match a list of
allowed addresses (set in the "ReplyFrom" variable), pass it to
sendmail as the "From:" address for the reply (with the '-f' option).
I often make aliases for myself so that my primary address is not
given out; if the alias gets out, I know who to blame. Unfortunately,
a reply to such a message would normally use the primary address
without this patch. A warning is displayed when this is going to
happen so that it can be modified with '~h'.
6) CC and BCC lists:
Allow '-c' and '-b' to accept white-space or ',' delimited lists.
Currently, a white-space delimited list of addresses work, but a
list of aliases will not get expanded. For example, currently:
mail -c "foo bar" christos
will fail to send mail to 'foo' and 'bar' if these are mail aliases
(in ~/.mailrc); sendmail aliases (in /etc/aliases) do work.
7) pipe command:
This pipes the current message into a shell command. I use this for
quick decoding of uuencoded mail, but I can imagine it might be
useful for decrypting encrypted mail, too.
8) show command:
This command takes a list of variables and shows their values. It
is probably stupid as the 'set' command without any argument
displays all variable values. Of course, if there are a lot of
variables you have to sift through the list for the one(s) you want.
data. This is useful when piping cron error output to mail. While I am
there add -~ to be a synonym for -I [but don't document it]. This is for
compatibility with other OS's.
