Re: which: command not found

On Fri, Dec 12, 2025 at 12:20 PM Bart Schaefer <[email protected]>
wrote:

> On Fri, Dec 12, 2025 at 8:39 AM Mark J. Reed <[email protected]> wrote:
> >
> > Why does the "command not found" output of `which` go to stdout?
>
> The most recent discussion of this starts at workers/43523 from 2018,
> at which point it was added to Etc/FAQ question 3.29.
>

! My bad for not checking the FAQ; it did not even occur to me as a thing
that would conceivably be there!

So the answer is "because csh did it that way and that's where zsh got the
'which' command". Well, I guess that's why zsh also borrowed `whence` from
ksh, which behaves more sensibly here.

I guess a consistent cross-shell approach here would be to use `type`,
check the return code, and extract the pathname from the end of the message
on success.

-- 
Mark J. Reed <[email protected]>