saved by backup with many snapshots

9.21: mis.cyb/fat32 sd card/corrupted:
(9.30: summary:
. only just months ago I started the policy of having
multiple backup snapshots instead of overwriting;
that turned out to be a life-saver, because,
to do overwrites safely,
you have to check every folder and file
to make sure none of them are corrupted .
)
. I tried saving html code to my sd card,
and it failed from both ko'edit and kompozer;
I thought it was a copy-protection trick ...
in fact, it's showing
everything in that folder is deleted!
log/psy now has zero items .

verifying corruption:
volume “SD2GB” ** /dev/disk2s1
** Phase 1 - Preparing FAT
** Phase 2 - Checking Directories
/PIM/2011/09 sep/0(cyb) has no clusters
/PIM/2011/09 sep/psy has no clusters
Marked 44 clusters as free
Free space in FSInfo block (141148) not correct (141192)
3306 files, 564768 KiB free (141192 clusters)

recovery by snapshot-backups:
oh, bak's are showing
those 2 folders have been empty for a while .
try a binary search:14, 17, 18 : ok?
18 14:17 is the last good;
cyb 15 9:37 (files: 15 18:48)
psy 15 18:42 (files 15 18:44)
the next is 19 18:58 -- both {psy, cyb} are missing .
cyb 19 17:50
psy 19 10:54 .

finding the cause:
. what was I doing when these changes got made?:
cyb 19 17:50
psy 19 10:54
. at 9.19.10:54 I was approaching mac,
but didn't do anything deliberate until 2 min later:

"( ... 10:56, gmail:0, log, ).

. maybe I jiggled the sd card, and lost the connection,
so it was like pulling it out without
giving the OS the warning it needed
to flush the caches and close the fs .
. at 9.19.17:50
I was about to break for some dictionary work;
1750 may have been at the time I started,
since I didn't give start-stop times for a 5-min job,
tho' it might have taken 10min

"( 17:50: this is the modify date of cyb.folder
getting corrupted . [9.21: found]
18:00?: used dictionary, )

. I remember being concerned that I was on a page
that did have ad's on it, but from the various browser logs,
{mac.safari, xu#main.vm, xu#wild.vm }
there was nothing around the time 19.18:00;
did I get ad's from mac.dictionary?
there were no ad's as I cycled through dict's history
but I think I was getting wikipedia from dictionary,
and then a link opened into safari .
. anyway,
pos.cyb/fs/sd card should be backup not primary:
. I'm working mostly from a vm,
so I keep my primary in a vmware shared folder,
and then backups happen with mac.timemachine .