re: kern/55103: /dev/wsmouse returns EINVAL

[matthew green <mrg%eterna.com.au@localhost>]

the problem is that in the past cat and hexdump were
useful and usable as "clients".  that no longer works,
because without the compat code available, there is no
way, without setting the version, to access these nodes,
which makes the cat/hexdump mehtods of debugging not work.

any argument that says "fix your userland" misses the 
desired (and traditional) operation here and is not a
helpful answer.

i think the only real solution we have here is the sysctl
that changes the default, and having the depend on whether
there is a path for compat or not -- eg, if it is present,
then use it, or if it's possibly available (MODULAR) then
use it, but with no baked in compat or modules, the default
should be the only working method.

AFAICT, this avoids breaking old userland with new kernel,
allows cat/hexdump to work, and keeps everything else
working in at least the same feature set as before.


.mrg.