Index: share/man/man7/ports.7
===================================================================
--- share/man/man7/ports.7
+++ share/man/man7/ports.7
@@ -25,7 +25,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd August 16, 2018
+.Dd June 24, 2020
 .Dt PORTS 7
 .Os
 .Sh NAME
@@ -390,6 +390,18 @@
 .Pa distfiles/
 in
 .Va PORTSDIR .
+.It Va SU_CMD
+An unprivileged user who has write access to
+.Va WRKDIRPREFIX
+and
+.Va DISTDIR
+is able to build a port.
+For configuration and installation, escalated privileges will be needed.
+Those are handled by the command defined by
+.Va SU_CMD
+which is
+.Ql /usr/bin/su root -c
+by default.
 .It Va PACKAGES
 Used only for the
 .Cm package