[PATCH] chg: handle EOF reading data block

[Yuya Nishihara]

On Tue, 19 Jul 2016 15:56:41 +0100, Jun Wu wrote:
> > Yeah, I have that patch to make commandserver channels thread safe. Do you
> > have any extensions that can share ui across threads?  
> 
> We have some "daemonize" code that use processes to build or rearrange cache
> in the background.

When parent and child processes write to ui.fout/ferr, they have different
stdio buffers and duplicated fds. So two writes won't be serialized even if
we do write(header + data) instead of write(header) + write(data).

> I think we may want some standard "daemonize" code in
> util to make sure stdios are closed.

Sounds good.