extsmail1
Robust sending of e-mail to external commands
Usage
extsmail [options ...]
Overview
extsmail masquerades as the standard UNIX sendmail(1) when messages are sent; effectively, it notes the command line switches passed to it, and puts those, and the message contents read from stdin, into a file in a spool directory for later sending with extsmaild(1).
Releases
Unchanged in 6 releases since Debian 7 (Wheezy).