macOS / binaries /

sendmail

/usr/sbin/sendmail
Postfix to Sendmail compatibility interface

The Postfix sendmail command implements the Postfix to Sendmail compatibility interface. For the sake of compatibility with existing applications, some Sendmail command-line options are recognized but silently ignored. By default, Postfix sendmail reads a message from standard input until EOF or until it reads a line with only a character, and arranges for delivery.

source: man