[zahlman]

> I suppose I should finally clear this up: The autocorrect functionality I originally described here was a feature of the first Linux systems I ever used, so I assumed it was how every Linux system worked by default. Since then I've come to understand that it's a completely optional extra doodad.

What systems did this? I've never encountered one that I can recall.

[shagie]

I recall from my early days of reading the jargon file... maybe DWIM? http://www.catb.org/jargon/html/D/DWIM.html (that said, someone who used that version would have many gray hairs... I was reading about this back in the early 90s).

    Warren Teitelman originally wrote DWIM to fix his typos and spelling errors, so it was somewhat idiosyncratic to his style, and would often make hash of anyone else's typos if they were stylistically different. Some victims of DWIM thus claimed that the acronym stood for ‘Damn Warren’s Infernal Machine!'.

    In one notorious incident, Warren added a DWIM feature to the command interpreter used at Xerox PARC. One day another hacker there typed delete *$ to free up some disk space. (The editor there named backup files by appending $ to the original file name, so he was trying to delete any backup files left over from old editing sessions.) It happened that there weren't any editor backup files, so DWIM helpfully reported *$ not found, assuming you meant 'delete *'. It then started to delete all the files on the disk! The hacker managed to stop it with a Vulcan nerve pinch after only a half dozen or so files were lost.

    The disgruntled victim later said he had been sorely tempted to go to Warren's office, tie Warren down in his chair in front of his workstation, and then type delete *$ twice.

    DWIM is often suggested in jest as a desired feature for a complex program; it is also occasionally described as the single instruction the ideal computer would have. Back when proofs of program correctness were in vogue, there were also jokes about DWIMC (Do What I Mean, Correctly). A related term, more often seen as a verb, is DTRT (Do The Right Thing); see Right Thing.

[ktm5j]

I'm on my phone so I'm too lazy to dig for this, but I'm pretty sure they're talking about the bit of shell script that gets run if you type a command that isn't found in PATH.

Fedora and Debian will both dive straight into searching apt/dnf for a matching package and ask "do you want to install this?"

I imagine you could create a hook that gets run for any command failure, but again I'm on my phone so not sure.

[VorpalWay]

This is generally called a command-not-found handler and are a feature of all the major shells (though the exact details differ, the general idea is to define a function with a specific reserved name), and most majors distros have ones that can be installed, even if they aren't by default.

I wrote my own (much faster) such handler for Arch Linux. I even wrote a blog post about the design: https://vorpal.se/posts/2025/mar/25/filkoll-the-fastest-comm...

[zahlman]

I thought of that, but TFA describes a system that trips on incorrect filenames rather than just incorrect commands.

[VorpalWay]

I vaguely remember that there are hook functions for processing all entered lines as well (at least for zsh), but it isn't something I have used myself so I know nothing more than that.

[dataflow]

It's https://packages.debian.org/sid/command-not-found

[ktm5j]

which is run by bash in the way I described.

In /etc/bash.bashrc:

# if the command-not-found package is installed, use it if [ -x /usr/lib/command-not-found -o -x /usr/share/command-not-found/command-not-found ]; then ... fi

[aflag]

I thought Ubuntu did that, but not Debian. Still, that's very different than what the author mentioned

[ktm5j]

Oh you might be right about Ubuntu vs Debian.. but I'm right about everything else I said. I went and looked at the source code.

[bandrami]

cachy's setup of fish tries to suggest commands (and even arguments) it might be, which I find terrifying and so turn off.

[iguessthislldo]

Zsh can suggest the corrections to commands and filename. I'm not sure if that's what they're talking about, but zsh has been around for awhile.

[dijit]

Anything that ships with a default zsh shell, which is a surprising number of distros actually.

[esseph]

Do any of the major ones?

Debian, Ubuntu, Fedora, Red Hat, etc. don't.

[zahlman]

Wikipedia:

> Zsh is available for Microsoft Windows as part of the UnxUtils collection and has been adopted as the default interactive shell for macOS, Deepin, and Kali Linux.

Mac is, in principle, a pretty big deal, but otherwise it isn't a common default.

[ninth_ant]

There are some bash options like cdspell or dirspell that are likely what the blog author is referring to.

Either that or they were using zsh with autocorrect preinstalled or had somehow rigged up the thefuck to execute and run on any error somehow? Either way seems like a terrible default.

[xg15]

Wasn't there an article on here a while ago that this "autocorrect" had a bug and was actually supposed to trigger only after several seconds of no user input, not immediately?