UnixStream is blocking

[Mygod]

Please use the one in tokio or async-std. While it seems like they implemented it using polling instead of signals (<aio.h>), it is better than blocking operations.

[Mygod]

Okay it seems like both of these two use mio, which uses <sys/select.h> underthehood, so I guess that is fine too.

[zonyitoo]

Which UnixStream? The one in src/relay/sys/unix/mod.rs:protect?

[Mygod]

I saw you are using tokio::net::UnixStream for stat_path... This is the correct one.

[zonyitoo]

Yup. @madeye said protect doesn't need to be nonblocked.

[Mygod]

While protect is basically a series of RPCs, why not just use nonblocking variant everywhere?

[zonyitoo]

It's true. I am going to add it for you. @madeye

[madeye]

Awesome 👍

[zonyitoo]

BIG PROBLEM: sendfd crate doesn't support async i/o.

Possible solutions:

1. Create a PR for tokio to support transferring FDs Support transferring FDs between processes for UnixStream and UnixDatagram tokio-rs/tokio#2322
2. Making a customized UnixStream all by myself.

[zonyitoo]

I chose 2. :P
Please @madeye help to test it for me, because I don't have any Android devices available.

[madeye]

Sure.

[Mygod]

I see. Technically SendWithFd is implemented by sendfd and not supported by stdlib. 6373040 seems like a good solution. 👍

[madeye]

6373040 works well. I think we can close this now.