NewDreamNetwork/ceph — comment on commit e43db381a23fc6fe670d2207d46303c423497796
File: src/global/signal_handler.cc line 85
By tv42:

The signal handlers are racy anyway.

1. it's not safe to do significant work in a signal handler; set a condition variable and return
2. you can't safely mix poll() and signal handlers without using the self-pipe trick

https://en.wikipedia.org/wiki/Unix_signal
http://evbergen.home.xs4all.nl/unix-signals.html
http://osiris.978.org/~alex/safesignalhandling.html
http://cr.yp.to/docs/selfpipe.html