S-nail is a mail processing system with a command syntax reminiscent of ed(1) with lines replaced by messages. It is intended to provide the functionality of the POSIX mailx(1) command and offers (mostly optional) extensions for line editing, IDNA, MIME, S/MIME, SMTP and POP3. It is usable as a mail batch language.
s-nail (mailx) is by far the fullest-featured Linux command line mailer going. Advanced addressing (cc,bcc), attachment handling and fully scriptable with vi/vim integration makes s-nail an outstanding command line mailing solution.