>One place where the inconsistency gets weird is when you use signalfd with epoll. The epoll will flag events on the signalfd based on the process where the signalfd was registered with epoll, not the process where the epoll is being used. One case where this can be surprising is if you set up a signalfd and an epoll and then fork() for the purpose of daemonizing -- now you will find that your epoll mysteriously doesn't deliver any events for the signalfd despite the signalfd otherwise appearing to function as expected. That took me a day or two to debug.

Is this what libuv does? I'm pretty sure it reads signals using epoll on linux, so in theory - if it does it this way - this bug could be be underlying all of node.js.