extsmail

Overview

extsmail masquerades as the standard UNIX sendmail program, reading messages, and piping them to user-defined commands until sending succeeds. It is particularly useful if you want to send email via commands that assume a fault-free network, for example via msmtp (to an external SMTP server) or ssh (to a server running a full sendmail-compatible MTA). extsmail is not a full SMTP server. It doesn't need root privileges. It can run as a daemon, or as a batch job (e.g. via cron). It is designed to have sensible defaults, and configuring it is a quick, one-off job.

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Credits

extsmail was originally created by Laurence Tratt. Olivier Girondel has been a major contributor since v1.8.