[csw-maintainers] Backing up the sudo binary

[Maciej Bliziński]

The current sudo package allows to deinstall it and lose the binary. If
a pkgutil upgrade fails after deinstallation, and before the
installation of sudo, you end up with a system with no sude. Here's an
idea:

- sudo preremove backs up the sudo binary somewhere on the filesystem
- sudo postinstall checks if the new binary is actually installed, and
 if so, removes the backup (the old binary might have a security risk)

This idea would help in my scenario, but has a drawback: when the
administrator wants to get rid of the sudo binary from the filesystem.
You run pkgrm, and the sudo binary remains somewhere in the system.

Is it enough to display a postrm message: "The sudo binary has been
backed up at $location, remove it manually if you really want to get rid
of it."

Thoughts?

Maciej