How do I install ports hands-off?

[Atom Powers]

For most ports I can pkg_add them to get them installed without
prompts. But for some ports I special make configurations that require
me to build the port from source. Usually I use portinstall for this,
but this causes problems if the make process requires additional
input.

How can I build a port using the default options, except those defined
in make.conf, without requiring me to confirm the option for each
port?

-- 
--
Perfection is just a word I use occasionally with mustard.
--Atom Powers--