Connections via sftp aren't considered interactive logins, thus.. are not registered via
utmp(5)/wmtp.
While you're free to look at the relevant man pages amscotti, they are a programming API.. not programs.
Sorry, but it's still easy to determine active connections with a little more.. work.
$ fstat | grep internet | grep "<--" | grep "sshd" | grep -v "root" | cut -d ' ' -f 1
It's a little primitive, but.. it'll get the job done.
