==== run-extent ====
awk -f /home/src/regress/sys/kern/extent/extest.awk /home/src/regress/sys/kern/extent/tests >extest.c.tmp
mv extest.c.tmp extest.c
cc -O2 -pipe   -MD -MP  -D_EXTENT_TESTING -DDIAGNOSTIC -c extest.c
cc -O2 -pipe   -MD -MP  -D_EXTENT_TESTING -DDIAGNOSTIC -c /home/src/regress/sys/kern/extent/../../../../sys/kern/subr_extent.c
cc   -o extest extest.o subr_extent.o 
./extest >extest.out
sed -n 's/ffffffffffffffff/ffffffffffffffff/;5,$p'  /home/src/regress/sys/kern/extent/extest.exp >extest.norm
diff -up extest.norm extest.out