feedmail-binmail-template

feedmail-binmail-template is a variable defined in `feedmail.el'.
Its value is

"/bin/mail %s"

Documentation:
Command template for the subprocess which will get rid of the mail.
It can result in any command understandable by /bin/sh. Might not
work at all in non-UNIX environments. The single '%s', if present,
gets replaced by the space-separated, simplified list of addressees.
Used in `feedmail-buffer-to-binmail' to form the shell command which
will receive the contents of the prepped buffer as stdin. The default
value uses /bin/rmail (if it exists) unless `mail-interactive' has been
set non-nil.

If you'd like your errors to come back as mail instead of immediately
in a buffer, try /bin/rmail instead of /bin/mail. If /bin/rmail
exists, this can be accomplished by keeping the default nil setting of
`mail-interactive'. You might also like to consult local mail experts
for any other interesting command line possibilities. Some versions
of UNIX have an rmail program which behaves differently than
/bin/rmail and complains if feedmail gives it a message on stdin. If
you don't know about such things and if there is no local expert to
consult, stick with /bin/mail or use one of the other buffer eating
functions.

The above description applies to "classic" UNIX /bin/mail and /bin/rmail.
On most GNU/Linux systems and perhaps other places, /bin/mail behaves
completely differently and shouldn't be used at all in this template.
Instead of /bin/rmail, there is a /usr/bin/rmail, and it can be used
with a wrapper. The wrapper is necessary because /usr/bin/rmail on such
systems requires that the first line of the message appearing on standard
input have a UNIX-style From_ postmark. If you have such a system, the
wrapping can be accomplished by setting the value of `feedmail-binmail-template'
to `feedmail-binmail-gnulinuxish-template'. You should then send some test
messages to make sure it works as expected.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.1 of Emacs.