means.
(2) Change MASTER_SITE_GNU etc. to use += instead of ?=, so users can
specify a local mirror in /etc/make.conf and still get the full
fallback in case something is missing.
Submitted by: Narvi <narvi@haldjas.folklore.ee>
(3) Skip port if USE_X11 or USE_IMAKE is defined and /usr/X11R6
doesn't exist.
Submitted by: imp
(4) Add "-" in front of rmdir of ${DISTDIR}/${DIST_SUBDIR} in
distclean target; the directory might not be empty because the
subdir is shared with some other ports' distfiles.