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Comment by gleenn | Hacker News Reader

One time I was flipping back and forth between directories, compiling some code, then checking it, then rm -rf'ing it. I accidentally hit up an cd ..'d one too many times. Suddenly the rm command hung and I was confused because it should be nearly instant as it was a few files. I stared in horror as I was accidentally deleting everything in mybhome directory. Luckily back then I had a .pr0n directory with a significant amount of content. A few things were lost but that .pr0n folder was luckily early enough in the list and big enough to slow down the deletion of my photos and documents. That's why I always recommend having a big "buffer" of video content for such situations, ya know, for data integrity ;)

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That's wild and inspirational. Like the scene in Rush Hour when a stack of bills saves Tucker from a bullet.

Though I'm moreso tempted to just create a `.1111aaaa-antidumb` directory and store my caches and backups there.

This has also un-inspired me from creating a fast `rm`-esque utility.

You could of course alias rm -rf to rm -rf -i

I always use trash-cli and alias rm to 'echo NO! #'.

Only if the file is too big to fit into the garbage bin, I can unalias rm, rm the thing and then reset the alias immediately after.

fwiw you can usually bypass aliases ad-hoc.

In Bash I believe instead of `ls` you can `\ls` to get the unaliased version.

You can also use the full path to the program, enclose it in quotes, or call "unalias ls" to disassociate it for that shell.

There is also safe-rm https://adamheins.com/blog/a-safer-rm

I thought -f cancels out -i, and when you alias "rm=rm -i", and then run "rm -rf" you get "rm -i -rf" and -f is last so it still wins.

That's why I always recommend having a big "buffer" of video content for such situations, ya know, for data integrity

Good idea, for safety of course. Just for completeness sake I would add one should not rely on that especially if they are using XFS and especially if using a hardware raid controller. The recursive rm may complete faster than the inodes are removed due to the nature how XFS among a few other filesystems operate in the background. I doubt many are using hardware raid controllers on their workstations but if one is on a server there is a chance there may be one and those will also perform some transactions in the background and one may get their prompt back sooner than the inodes have actually been removed. This is all edge case off course. People should have a massive .pr0n folder regardless.

Great idea, I shall see to it right away.

Userpace pronfs provides high latency unlinking?

Turns out that pronfs uses fsck in the background to provide the delay

Unless you were using tcsh you had to rewrite your shell configuration though.

rm has a --preserve-root option that's enabled by default, which prevents you from removing / . I wish it had a --preserve-home option too.

Seriously, start using trash-cli. Even Windows from 30 years ago had a recycle bin.

I can’t grasp how “power users” like Linux users are stuck working in primitive environments.

Nah, recycle bin is the wrong model. Automatic filesystem snapshoting is the way to go. Snapshots are cheap and let you recover full state from your history.

Just use btrfs, and set up btrbk to snapshot your home directory every 5 minutes, and have its gc keep every snapshot from past few hours, an hourly snapshot for past few days, and weekly for past few months.

I wish filesystems had a first-in, first-out "garbage heap" model.

The problem with snapshots is that they take up space. The trash has the same issue, with the added drawback that you have to think about emptying it, and if you empty it before realizing you made a mistake, it won't help you.

With a "garbage heap" model, all deleted files would automatically end up on the "heap" when deleted. The heap would be exactly as large as the amount of free space you have left, and shrink when necessary by deleting the oldest files, perhaps with a minimum size (expressed in days) that would require manual action to shrink beyond.

Snapshots on ZFS only take up space when files change. It's easy to use one of the many snapshot managers to accomplish what you want - I do it for my workstation and laptop. I have zero fear of deleting files, upgrading the OS, making sweeping changes to my system config, etc.

On a CoW filesystem like btrfs/bcachefs/zfs, a snapshot only has the overhead of the delta, so are cheap.

Btrbk can also take disk space into account for garbage collecting snapshots? Not sure.

There would still have be some buffer between the amount of space you have left and the size of this heap - even if the OS were changed to treat this specific case as not being out of disk space, it would significantly impact write performance on the disk once it is 'full', because any disk operation would have potentially double the number of operations required compared to being able to write it to empty space on the disk

Snapshots of home directories grow to ridiculous amount due to trash that piles inside of it. Off the top of my head:

- ~/.local/share/docker is 29G of data that continuously mutates. - Rust/Cargo produce "target" directories in $PWD whenever they run, which is gigabytes of crap littered all over the place.

Keeping snapshots of home would take up a huge amount of disk space, especially if you ever want to keep more than one.

That said, keeping TWO snapshots for 24hs for "un-deleting" files might be an interesting idea.

I personally only snapshot Documents, Pictures, my git repo dir, etc.

Stuff like .cache and podman stuff stays unsnapshotted.

I just recommend to others to snapshot home since most people don't want to bother categorizing their data.

Recycle bin is just a different model. I have full disk weekly and homedir daily backups and could use live snapshots too, but it’s just easier to dig into the bin sorted by deletion date.

If you delete things from a file manager in Linux, they all generally go into the Trash too.

And if you rm/del/Remove-Item on Windows, it will also delete without sending to the recycle bin.

You're way too trusting of trash-cli here. I switched to it a while back and the only time I actually needed to recover something half the files in the folder weren't in the rubbsih bin, they were just gone

Fuck recycle bins. Make proper backups.

When I delete something I want it deleted. If I make a mistake I grab it from a backup or just re-obtain it.

This is the best comment I've read on Hacker News in a long time

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