May 26, 2018
Tools for passing mail across serial links
serialmail is a collection of tools for passing mail across serial links. It works with qmail you use qmail to deliver messages to a maildir, and then serialmail to deliver messages out of the maildir.
serialmail uses ucspi-tcp/tcpclient for networking. It can also be used with future UCSPI clients for transparent compression, IPv6, etc.
serialmail supports SMTP, including ESMTP PIPELINING, and QMTP.
serialmail is under user control. A user delivering messages to a maildir, and picking up the messages through qmail-pop3d, can switch to maildirsmtp without pestering the sysadmin. The user can also decide whether undeliverable messages should be left for POP retrieval or bounced back to the sender.