[zeromq-dev] [RFC] systemd socket activation for libzmq

[Jim Garlick]

On Mon, May 30, 2016 at 09:57:00PM +0200, Michal Vyskocil wrote:
> Hi,
> 
> Awesome, the fact czmq handles that is good enough for me. Closed the
> request.
> On Mon, 2016-05-30 at 21:14 +0200, Michal Vyskocil wrote:
> > Hi,
> >
> > Ale's thread about Setting privileges on a UNIX socket inspired me to
> > create small patch to libzmq adding automatic systemd socket
> > activation support.
> > https://github.com/zeromq/libzmq/pull/2015
> >
> > Right now the feature is fairly minimal - limited to ipc transport -
> > and tested manually using malamute broker. I would like to hear any
> > feedback. If you consider it as useful (or want to avoid dependency on
> > the most hated OSS software on the planet ;-)), please say so.
> 
> Hi,
> 
> That functionality is already implemented for both IPC and TCP sockets.
> 
> The low level library has the ZMQ_USE_FD socket option to pass a file
> descriptor, and the high level CZMQ has ZSYS_AUTO_USE_FD env var or
> zsys_set_auto_use_fd(1) function to let zmq automatically match
> endpoints to the corresponding sockets managed by systemd. As long as
> the metadata matches (eg: file path for IPC, address + port for TCP), it
> will just work out of the box.
> 
> Kind regards,
> Luca Boccassi

Somehow I missed that - sounds useful!

Is the usual reconnect behavior disabled when this option is present,
or is that what the aforementioned metadata is used for?  I couldn't
find the answer in
  http://api.zeromq.org/4-2:zmq-setsockopt

or in the note about reconnect exceptions in
  http://api.zeromq.org/4-2:zmq-connect

Thanks,

Jim Garlick