Command not found handler

John Allsup

4/18/24, 10:55 AM

Apologies if this has been asked before, but it's basically impossible to search for.

When I type e.g. wibble at the bash prompt, it prints

Command 'wibble' not found, did you mean:
  command 'wobble' from deb emboss (6.6.0+dfsg-11ubuntu1)
Try: sudo apt install <deb name>

Now what I'd like to know is where is this handler and can I replace it with my own script. For example if I were to paste a github url at the command line with no 'git clone' before it, then expand it to 'git clone', and other urls launch in Chrome, or whatever.

I can't find where this 'command not found' hander is, but I suspect it's a script somewhere that gets hooked into bash.

1 + 2

bash

guiverc

4/18/24, 11:10 AM

https://launchpad.net/ubuntu/+source/command-not-found *you didn't provide a release and I'm not going to look up the package version for `emboss` thus the link I provided.. Had I had a release I'd have provided link that was easier & showed the files involved... (*but you can follow links yourself*)

Cyrus

4/18/24, 6:29 PM

`set -x; wibble; set +x`?

Score:2

Ubuntu

steeldriver

4/18/24, 11:09 AM

The handler itself is a shell function:

$ declare -f -p command_not_found_handle 
command_not_found_handle () 
{ 
    if [ -x /usr/lib/command-not-found ]; then
        /usr/lib/command-not-found -- "$1";
        return $?;
    else
        if [ -x /usr/share/command-not-found/command-not-found ]; then
            /usr/share/command-not-found/command-not-found -- "$1";
            return $?;
        else
            printf "%s: command not found\n" "$1" 1>&2;
            return 127;
        fi;
    fi
}

The default handler in Ubuntu is defined in the /etc/bash.bashrc file. In turn, /usr/lib/command-not-found is a Python script provided by the command-not-found package.

+ 1

John Allsup

4/24/24, 7:09 PM

Thanks. Exactly what I was after.

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Command not found handler

Post an answer

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