help for extract "extension" from filename and print it with filename

[lacsaP Patatetom]

hi,

I would like to extract the "extension" of the filename and print these two
pieces of information.
I use `gawk` very occasionally and have done a few searches on the internet
without success.

I use `ntfsundelete` like this :
```
$ ntfsundelete -f -p 100 -t 1m -S 1k-4m /dev/nvme0n1p2 | head
Inode    Flags  %age     Date    Time       Size  Filename
-----------------------------------------------------------------------
1772     FN..   100%  2024-03-12 18:45     32768  EventStore.db-shm
2705     FN..   100%  2024-03-12 18:45     32768  EventStore.db-shm
2755     FN..   100%  2024-03-12 19:48     32992  EventStore.db-wal
2757     FN..   100%  2024-03-12 18:45     32768  EventStore.db-shm
2774     FN..   100%  2024-03-12 18:45      3936
 2031232367709955654_trigger.dat
2904     FN..   100%  2024-03-12 19:46      1236
 6258807092785928627_data.dat
6603     FN..   100%  2024-03-12 18:45      1864
 2031232367709955654_data.dat
6659     FN..   100%  2024-03-12 19:49   2925232  mpenginedb.db-wal
```

and I would like to print something like this :
```
db-shm EventStore.db-shm
db-shm EventStore.db-shm
db-wal EventStore.db-wal
db-shm EventStore.db-shm
dat 2031232367709955654_trigger.dat
dat 6258807092785928627_data.dat
dat 2031232367709955654_data.dat
db-wal mpenginedb.db-wal
```

so I try this with `gawk` but
1) filename is not printed
and
2) I have an error :
```
ntfsundelete -f -p 100 -t 1m -S 1k-4m /dev/nvme0n1p2 | head | sed 1,2d |
awk '{ext=$7;sub("^.*\\.","",$ext);print $ext, $7}'
db-shm
db-shm
db-wal
db-shm
awk: cmd. line:1: (FILENAME=- FNR=5) fatal: field.c:134:grow_fields_arr:
fields_arr: cannot reallocate -2196885132029906936 bytes of memory: Cannot
allocate memory
```

apart from me ;-), what's the problem ?

regards, lacsaP.