Sometimes I start a program that takes a very long time to finish (emerge), then realize that I should go to bed instead of waiting for it. If I know this in the first place I would run program; halt ...
So cron or at can schedule our commands to run at the exact time we need them to, but can we schedule commands to run when systems are inactive? Something like: echo "some_commands" | when 'cpu ...
If I setup cron jobs incorrectly they appear to silently fail. Where should I look for an error log to understand what went wrong?