Mark Oteiza <mvoteiza@udel.edu> writes:

> mpc.el treats MPD_HOST only as an address or hostname, when it can also
> be a socket. So, doing ‘M-x mpc RET’ here gives
>
>     /run/user/1000/mpd/socket/6600 Name or service not known
>
>>From the mpd manual:
>
>     bind_to_address <ip address or hostname or any>
>            This specifies which address mpd binds to and listens on.
>            Multiple bind_to_address parameters may be specified.  The
>            default is "any", which binds to all available addresses.
>
>            You can set a port that is different from the global port
>            setting, e.g.  "localhost:6602".  IPv6 addresses must be
>            enclosed in square brackets if you want to configure a
>            port, e.g. "[::1]:6602".
>
>            To bind to a Unix domain socket, specify an absolute path
>            or a path starting with a tilde (~).  For a system-wide
>            MPD, we suggest the path "/var/run/mpd/socket".
>
> ‘bind_to_address’ is the mpd config option corresponding to MPD_HOST.

Here's a patch for handling the MPD_HOST being a socket.  I don't really
get the wording "or a path starting with a tilde (~)." because no mpd
clients that I have (mpc, ncmpcpp) actually do tilde expansion
themselves, so I ignored that case.