If your port requires user input to build, configure, or install, you must set IS_INTERACTIVE in your Makefile. This will
allow ``overnight builds'' to skip your port if the user sets the variable BATCH in his environment (and if the user sets the variable INTERACTIVE, then only those ports requiring interaction are built). This will
save a lot of wasted time on the set of machines that continually build ports (see
below).
It is also recommended that if there are reasonable default answers to the questions,
you check the PACKAGE_BUILDING variable and turn off the
interactive script when it is set. This will allow us to build the packages for CDROMs
and FTP.
