* unixlib is not easy to use outside of wine itself * FIFO is not better as it require unixlib
I'm not talking about unixlib. The whole point of this exercise is to communicate between a Wine process, and a host process that is not run through Wine. I'm saying you can create a named FIFO from the host Unix process and open it from the Wine process like a normal file. For that matter, you can do the same thing with a non-abstract named Unix socket, which we can just write to as if they were normal character devices—you don't need AF_UNIX support in Wine for that.
* socket is a big no no as sockets can't filter by user id
It took me a second to realize what you mean. I assume what you're trying to say is "IP sockets won't work, because we want to prevent other users on the same machine from accessing the socket". That makes sense as a restriction. -- https://gitlab.winehq.org/wine/wine/-/merge_requests/2786#note_51567