macOS / binaries /

postfix-wrapper

/usr/libexec/postfix/postfix-wrapper
Postfix multi-instance api

By default, the postfix command operates in single-instance mode. In this mode the command invokes the postfix-script file directly. When the postfix command operates in multi-instance mode, the command needs to execute start, stop, etc. commands for each Postfix instance.

source: man