rc settings

Ted Drain <ted.drain@...179...> writes:

Something else that might be useful is to put a RC file version
number in the RC file itself [...] If you're more ambitious, you can
write RC file version converters so that older versions are
auto-converted (and maybe even auto-updated) to the current version
when used.

The simplest possible implementation doesn't require much: perform a
three-way merge (using e.g. diff3 or merge, if present on the system)
with the old version of the default rc file as the ancestor, and the
new default rc file and the user's rc file as the modified versions.
If there are any conflicts, let the user handle them.

I suspect that the usual reason for getting rc warnings is that the
user neither knows nor cares about the changed options; if the options
have the old default values, it's probably safe to change them to the
new defaults.