UdpSocket is missing close_{read,write}

[alexcrichton]

These weren't added recently, and I don't think there's a fundamental reason for not offering this, so we should probably offer it.

[LorenVS]

I began working on this issue. My work in progress is at 68bf86e. It seems like getting libnative working properly won't be that difficult but I'm pretty lost when it comes to libgreen. Any pointers on what is necessary there?

[alexcrichton]

The relevant file would be src/librustuv/net.rs and I would take a look at the implementation for TCP streams. You'll also find some relevant bits in src/librustuv/timeout.rs and src/librustuv/stream.rs (although timeouts may not be too relevant).

Thinking about it a bit, I'm not sure if it makes sense to provide a close_write method because I'm not sure that UDP can actually block in a call to sendto. There's no acknowledgement of a packet being sent, so I'd be under the impression that it's a fire-and-forget situation.

[LorenVS]

Would it be preferable to just replace close_read/close_write with a single close that uses SHUTDOWN_BOTH?

[alexcrichton]

A single close method has a weighty name and raises questions why none of the other I/O primitives carry the same method. It may be best to add an #[unstable] close_read method for now because we're likely to keep the functionality but may want to change the name in the future.

[alexcrichton]

This is being handled by rust-lang/rfcs#807.

[LorenVS]

I think this issue might need to be re-opened... As part of the IO reform, I believe a shutdown method was supposed to be added to UdpSocket (the docs for std::io::Shutdown mention that it should exist). However, the method doesn't exist yet, and rfc 807 appears to be closed

[alexcrichton]

Oops yes this is definitely an oversight, I've opened a new issue as this isn't quite appropriate any more.