On Fri, Dec 31, 2021, 10:54 AM Adam Thornton <athornton@gmail.com> wrote:

> Slightly older, but also slightly more fundamental to the system, you need
> look no farther than Solaris's `/bin/sh` for an illustrated example of the
> pros and cons of maintaining backwards compatibility. [snip]
>

Sun is not the exemplar here: the move from SunOS 4's BSD userland to
Solaris 2's SVR4 broke tons of things. They didn't seem to mind that their
customers had to pay the cost of adaptation.

The Linux example is also a bit strange. The move from e.g. `ifconfig` and
`netstat to `ip` and `ss` required lots of local retooling (I suppose some
distros retain the older tools or let you install them as an option. I
suppose one could always install `bash` on Solaris as a shell lingua
franca, as well). Not to mention systemd. The point is, breaking changes
are introduced all the time.

        - Dan C.