Re: Future of /usr/bin/which in Debian?

[Clint Adams <clint@debian.org>]

On Wed, Aug 18, 2021 at 08:50:04PM +0200, Ben Hutchings wrote:
> 3BSD first implemented 'which':
> <https://minnie.tuhs.org/cgi-bin/utree.pl?file=3BSD/usr/man/man1/which.1>
> (1979).  This was csh-specific and I think it later became built-into
> csh.
> 
> FreeBSD 2.1 introduced a new non-built-in implementation:
> <https://www.freebsd.org/cgi/man.cgi?query=which&apropos=0&sektion=0&manpath=FreeBSD+2.1.0-RELEASE&arch=default&format=html>
> (1995).  This was written in Perl and then rewritten in C a few years
> later.
> 
> Debian's implementation started out in 1995 or 1996 as a shell script
> calling 'type', and remains a shell script.
> 
> Red Hat has yet another implementation:
> <https://www.freebsd.org/cgi/man.cgi?query=which&apropos=0&sektion=0&manpath=CentOS+7.1&arch=default&format=html>,
> <https://carlowood.github.io/which/> (1999 or earlier).  This is
> written in C.
> 
> So 'which' has a very long history in csh, which was the default
> interactive shell in many versions of Unix.  Its availability to other
> shells dates back to the 90s (at least) but is not portable due to
> there being multiple very different implementations.

I'm happy to transition /usr/bin/which to alternatives if people are
interested in packaging all of these.