bug#6781: emacs server with X11 build on OSX

[Ken Raeburn]

On Aug 2, 2010, at 16:22, Juanma Barranquero wrote:

> (I'm Cc:ing this to bug-gnu-emacs to create a bug report.)
> 
> On Mon, Aug 2, 2010 at 17:56, Leo <sdl.web@gmail.com> wrote:
> 
>>> (make-network-process :name "server" :server t :family nil :service t
>>> :host 'local)
> 
>> I have used the following in server-start as workaround:
>> 
>>  (make-network-process :name "server" :server t :family 'ipv4 :service t)
> 
> If ":family 'ipv4" works and ":family nil" does not, that surely means
> that Emacs is chosing ipv6. Does server.el work with the attached
> patch?

There was one more difference, which was that your suggestion included ":host 
'local" and his workaround did not.

Using ":host 'local" causes the C code to look up the name "localhost", which 
may or may not map to IPv4 and/or IPv6 addresses.  (Almost always an IPv4 
address of 127.0.0.1; sometimes IPv6 also, and I've occasionally seen it mapped 
to the local ethernet interface's IPv4 address.)  Not specifying the host at 
all causes a wildcard address to be used, which would be reachable from other 
hosts, whereas 127.0.0.1 generally is not.  (Actually, in the version I'm 
looking at, which isn't quite current, it causes INADDR_ANY to be used, which 
looks like a bug if the address family is not specifically given as AF_INET.  
I'll try to look at that a little closer if I get some time next weekend.)

> I don't know whether that means that your system is set up only for
> ipv6, or that it has both ipv6 and ipv4 and make-network-process is
> selecting ipv6 for `localhost'. In any case, server.el / emacsclient.c
> are not adapted to ipv6, so forcing ipv4 seems right for the moment
> being.

Yes.

Ken