too, if it's available and O_NOATIME is too.
* what do we do elsewhere about _GNU_SOURCE?
- - tweak the short options. I think dump files should be a
- second-class feature in general, so that --dump and --load should
- be represented by capital options. That leaves -d free to be
- --depth, which I think is more generally useful.
- * while I'm tweaking the options list, "[all modes]" ought to
- say "[most modes]", due to --scan-dump.
-
- New mode: --remove, to destroy the data file. Handy for
totally self-contained usage: "-s . -w -R".