> [...], you do indeed seem to think that async-mounted Unix-based > filesystems should be able to be repaired, at least some of the time,
There's a huge difference between "this isn't promsied" and "this never happens". They _can_ be repaired...some of the time. When they can, it is because, by coincidence, it just so happens that the stuff that got written produces a filesystem fsck can repair. > The probablility of any Unix-based filesystem being repariable after > a crash is zero (0) if it has been mounted with MNT_ASYNC, and if > there was _any_ activity that affected its structure since mount time > up to the time of the crash. This is simply false. I just tried it. On a 5.1 i386 system, I used fdisk and disklabel to make a half-gig partition, newfsed it, mounted it normally, copied a file into it, unmounted it, mounted it async, removed the file, and hit the power switch. After the machine came back up, I tried fsck on the filesystem. It said it was clean. I used fsck -f. It was happy. I mounted it and, as far as I can tell, fsck was correct in thinking the filesystem was OK. So, there is an existence-proof-by-example that there are circumstances under which a filesystem mounted async can be changed and still be left in a state fsck can repair. > It still might survive after some types of changes, but it _probably_ > won't. Right. But that's not "probability ... is zero (0)". > Linux ext2 is not a Unix-based filesystem and Linux itself is not a > Unix-based kernel. It's about as Unix-based as NetBSD is. Unless you mean something strange by "Unix-based" - what _do_ you mean by it? > For Unix-based filesystems and their repair tools, any probablility > of recovery less than one is as good as if it were zero. That's not how I feel about it when I've lost a filesystem. I'll take a filesystem with a nonzero probability of recovering something useful from over one that guarantees to trash everything any day (other things being equal, of course). /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mo...@rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B