Consider deprecating packetfs (pex)

[klange]

packetfs (or pex) is our very old packet-based IPC mechanism, originally developed for Yutani all the way back in 2014 to replace a system that used file descriptor sharing to connect clients with dedicated pipes. The packetfs API was built long before we had a socket layer, and it works very differently from typical sockets.

Our current users of packetfs are still the compositor, as well as the splash log daemon and the toast notification daemon.

Toast users reference it directly, but there's very few of them (the panel network widget, and some Kuroko scripts).

Splash log users also reference it directly, with startup scripts simply echoing to it.

Windowing clients all go through libtoaru_yutani, which adequately hides the interface.

All of these users would likely be sufficiently served by a local UDP service (local UDP would maintain ordering and have delivery guarantees, but lack connection state, so we'd need to handle that separately...), though implementing real Unix domain sockets may be more prudent.

Porting Yutani to a standard IPC interface would bring us one step closer to running the compositor on other OSes.

[klange]

We do use pex_broadcast in a few places in the compositor, but we don't really need to do that since we maintain a list of connected clients separately...

[IAmTheNerdNextDoor]

Porting Yutani to a standard IPC interface would bring us one step closer to running the compositor on other OSes.

Honestly, I've always wanted the Yutani compositor (or even the entire ToaruOS desktop interface) on Linux or FreeBSD or maybe even nested on macOS. It'd be awesome and I hope this happens!

[klange]

I've wanted to get the compositor running as an SDL app on other platforms for a while myself, but it's been very low on the list of priorities.

There was actually a port of Yutani to use Unix domain sockets and shared memory, by Sortie, of Sortix fame, and we had it running under Sortix for a bit. But as far as I know that port is lost, and it was a long time ago and the compositor has changed a lot since then.

[IAmTheNerdNextDoor]

I've wanted to get the compositor running as an SDL app on other platforms for a while myself, but it's been very low on the list of priorities.

I think there'd be quite a bit of interest around that if you or someone else ever makes it an app or a proper desktop compositor outside of Toaru. It all comes down to who has free time and enough drive behind it to actually port Yutani to either of those in the end.

There was actually a port of Yutani to use Unix domain sockets and shared memory, by Sortie, of Sortix fame, and we had it running under Sortix for a bit. But as far as I know that port is lost, and it was a long time ago and the compositor has changed a lot since then.

Ah, that's pretty cool, it's a shame that the port is lost though.

(You've actually got me into thinking about trying to port Yutani as a nested app which I really want to do now. I doubt I'll do anything or even get anywhere if I start, but worth a shot if I do try. ¯\_(ツ)_/¯)