$BTRFS_TUNE_PROG -S 1 $seed
_mount $seed $SCRATCH_MNT >> $seqres.full 2>&1
cat /proc/self/mounts | grep $seed >> $seqres.full
-$BTRFS_UTIL_PROG device add -f $sprout $SCRATCH_MNT
+$BTRFS_UTIL_PROG device add -f $sprout $SCRATCH_MNT >> $seqres.full
cat /proc/self/mounts | grep $sprout >> $seqres.full
# check if the show_devname() returns the sprout device instead of seed device.