- I had a lost+found folder in all Unix file systems I used since the 80s. It's where fsck places files that it found during a scan and can't figure out to which directory they belong. Sometimes I found stuff in there.
From what I googled XFS, Btrfs and ZFS don't use lost+found. It's a thing of the old not journaled filesystems and of the ext family.
- I have a book on my bookshelf, Eric Foxley's Unix for Super-Users. It was published in 1985, and it answers this question on page 52, the first page listed for the entry 'lost+found' in its index.
This is surely not the earliest book mention, is it? (It'll be in earlier man pages, of course.) Google Books does not give me an earlier one, although it does yield another 1985 book.
Fun fact: Foxley cautioned that lost+found must be pre-sized ahead of time, because the fsck of the time did not grow the directory to fit found files.
by FerretFred
9 subcomments
- In a couple of decades running Linux installations of all flavours, I have never seen anything in lost+found!
- The lost+found folder saved our backs once way back when. We had a 1TB NAS running Linux, an enormous amount of storage back then. It was shut down unexpectedly and disorderly and ran a multi hour fsck upon reboot. The volume must have had a shot root inode, as after the machine booted and mounted the volume it was empty. All directories were luckily under lost+found with all their contents.
by NelsonMinar
0 subcomment
- We once deleted the lost+found folder on an old Unix system* by accident. Things went very badly the next time the system rebooted, fsck did not handle it at all well.
* Probably DEC Ultrix 2.2, a BSD 4.2 derivative.
- Why can't a filesystem create the lost+found folder only when it needs to store files in it?
That would be a much cleaner approach, imho.
Added benefit is that you'd immediately see it if something is wrong with a disk.
- Back in the day I accidentally deleted all my stuff because I had it all in a special dir of this user in suse Linux. When I deleted the user, yast deleted everything.
Fortunately I was using ReiserFS at the time and something about its murderous tree data structure made it trivial to undelete.
Reiser_fsck found ALL my stuff, mostly with full dir tree structure in tact and put it all in lost+found
- (2012), maybe?
- This is the way journaled filesystems place recovery files.
- lost+found is still used on OpenBSD, seems it is created when needed. Only /home has that directory on my system. IIRC, it was created when a kernel panic happened a few releases ago. Plus some files were placed in it when fsck executed on /home
- glad to see that Stack Overflow (or stackexchange.com) is still a thing.
by shevy-java
0 subcomment
- I keep everything hidden there.
In reallife I would rename this to "trash".
by undebuggable
2 subcomments
- lost+found is the Thumbs.db and .DS_Store of Linux
by account42
1 subcomments
- rmdir /lost+found is always my first step after creating and mounting a new file system. Reserving a user-visible directory just so that a 0.00001% chance recovery is slightly easier just doesn't make any sense.
- How do questions like this make it to the top? It is an obvious thing if you search for it or ask AI, but people seem to just ignore those in favor of generating new human responses.
Thing is, any time I try to replicate something like that, I basically get a flippant response saying to go look elsewhere.
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