udp fd write event

[zuobeixing]

Hi，I have a doubt，Usually the udp connection is always writable，but If I add the udp connection write event to epoll via ev_io_start, then when can trigger a writable event ?

[dr-begemot]

I think, that writable event will triggered, when you write somethings to udp connection fd.

[liuye0331]

Why not write a test code to find out what will happen.