daemons can't show the backtrace of rb_bug
Ruby shows backtrace and other information into stderr on rb_bug.
But daemon process redirects stderr into /dev/null.
How do I get the log?
NOTE: if I can reproduce this, I can use strace to get it. But issues are not always reproducible.
Updated by normalperson (Eric Wong) about 5 years ago
I always recommend pointing stderr to a regular file using
IO#reopen after daemonization. Perhaps kwargs may be added
to Process.daemon to encourage this usage?
Process.daemon err: '/path/to/stderr.log', out: '/path/to/stdout.log'