allocated, as noticed by Chuck Cranor. In addition to re-arranging
the assignment as suggested by Niklas Hallqvist, check to see if maxproc
is higher than the number of available user PTs. If it is, lower maxproc
to that value, the rationale being that it's much more desirable to have
fork() return EAGAIN than to have your system wedge.
XXX note that root can still raise maxproc with sysctl(2) later. It's
probably worth having further discussion about this issue, but until
everyone has time to think about it, this seems like an acceptable solution
for the time being.