Variable: message-mailer-swallows-blank-line
message-mailer-swallows-blank-line is a customizable variable defined
in message.el.gz.
Value
nil
Documentation
Set this non-nil if the system's mailer runs the header and body together.
(This problem exists on Sunos 4 when sendmail is run in remote mode.)
The value should be an expression to test whether the problem will
actually occur.
Source Code
;; Defined in /usr/src/emacs/lisp/gnus/message.el.gz
;; Note: could use /usr/ucb/mail instead of sendmail;
;; options -t, and -v if not interactive.
(defcustom message-mailer-swallows-blank-line
(if (and (string-match "sparc-sun-sunos\\(\\'\\|[^5]\\)"
system-configuration)
(file-readable-p "/etc/sendmail.cf")
(with-temp-buffer
(insert-file-contents "/etc/sendmail.cf")
(goto-char (point-min))
(let ((case-fold-search nil))
(re-search-forward "^OR\\>" nil t))))
;; According to RFC 822 and its successors, the field name must
;; consist of printable US-ASCII characters other than colon,
;; i.e., decimal 33-56 and 59-126.
'(looking-at "[ \t]\\|[][!\"#$%&'()*+,./0-9;<=>?@A-Z\\^_`a-z{|}~-]+:"))
"Set this non-nil if the system's mailer runs the header and body together.
\(This problem exists on Sunos 4 when sendmail is run in remote mode.)
The value should be an expression to test whether the problem will
actually occur."
:group 'message-sending
:link '(custom-manual "(message)Mail Variables")
:risky t
:type 'sexp)