This changes the buildlink3.mk files to use an include guard for the
recursive include. The use of BUILDLINK_DEPTH, BUILDLINK_DEPENDS,
BUILDLINK_PACKAGES and BUILDLINK_ORDER is handled by a single new
variable BUILDLINK_TREE. Each buildlink3.mk file adds a pair of
enter/exit marker, which can be used to reconstruct the tree and
to determine first level includes. Avoiding := for large variables
(BUILDLINK_ORDER) speeds up parse time as += has linear complexity.
The include guard reduces system time by avoiding reading files over and
over again. For complex packages this reduces both %user and %sys time to
half of the former time.
utilities. Blurb:
The bsdav package contains programs for reading and writing audio
and video. The programs use BSD-native devices. Naturally, the
source code is BSD-licensed as well. These programs depend on
the libbsdav library for both accessing audio(4) and bktr(4) devices.
(Hopefully, more documentation will be written soon on how to use
the functions libbsdav contains!)
While one of the goals of the bsdav project is simplicity, another
goal is to make A/V processing on BSD systems easily accessible.
Moreover, to ease the storage and synchronization of both audio
and video streams, bsdav has it's own, very simple, A/V container
format.
Hopefully the bsdav programs are clear and correct enough such that
they help others understand how to use audio(4) and bktr(4).
