build (ng7):
  cc -O -DUSE_NG7 -I/usr/src/lib/libnetgraph7 -I/usr/src/sys -o /root/vjc_oob_leak7 \
     /root/vjc_oob_leak7.c /usr/src/lib/libnetgraph7/sock.c /usr/src/lib/libnetgraph7/msg.c /usr/src/lib/libnetgraph7/debug.c
exit 0 (trivial warnings only)