which init thoughtfully revoke()'s when starting a getty on ttyv0. This
Cron's popen() was passing these fd's through to cron children (ie:
sendmail, *not* normal cron jobs). The side effects were usually
not noticed, but it tripped up postfix which did a sanity check to see
that stdin/out/err were open, and got EBADF even thought the fd's were
in use. I seem to recall sendmail itself has hacks to work around
this problem, it had a checkfd012() function, possibly for this same
problem. (Postfix has a workaround too now though..)
This is a hack, not a fix. It's probably best to check and perhaps
close/reopen() /dev/console if needed each time around the event loop.
It would probably be useful to actually see any error messages from cron.
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