TcpListener::bind example gets stuck in an infinite loop for non-privileged users

[glandium]

It's just using the trait implementations for IoResult<T>, and not handle the errors, so the repeated .incoming() calls all return None immediately, meaning the loop makes no progress.

It would preferably handle the errors, or at least mention that this might happen.

Old description:

Stuck on TcpListener::bind when the underlying bind() syscall fails

Taking the example on http://doc.rust-lang.org/std/io/net/tcp/struct.TcpListener.html and running it as non privileged user (which can't bind port 80) leads to the program stuck on TcpListener::bind according to gdb. Strace shows the bind() syscall returning EACCES, but the rust program just doesn't move or errors out, or whatever. The same happens for EADDRINUSE.

[sfackler]

What OS and rust version? rustc --version should give that info.

[alexcrichton]

Closing, this is just the specific example itself. It's not suck in bind, but rather suck in an infinite loop. The for loop in the example is continuously yielding errors which are being ignored.

[huonw]

Reopening, because I think the example should either mention that, or handle errors properly, because I'm sure @glandium isn't going to be the only one to hit this.

[huonw]

(I updated the title/description.)

[ben0x539]

Maybe incoming should return an empty iterator if called on a an IoResult that's Err(...)?

[glandium]

Maybe the example could use try!

[steveklabnik]

Is this still a relevant issue?

[ben0x539]

It still reproduces.

Using the transparent trait implementations on IoResult like this seem like fairly opaque style.

[aturon]

cc me

[steveklabnik]

With new io, this now fails on the unwrap.