如何从os.Error获取os.Errno？ 其他使用os.Timeout的方式吗？

Question

The net.Conn interface provides the SetTimeout methods and I am supposed to check the returned error with os.Timeout. However I see no way of calling os.Timeout on the returned os.Error.

(The os.Error I've got is read unix @: Resource temporarily unavailable which seem to consists of two parts: description of the function which timed out and the strerror description of the EAGAIN. I've tried err == os.EAGAIN and it doesn't work, probably because of the extra information in os.Error).

Answer 1

You need to do a type assertion. Let's say kon is type net.Conn and you read into buffer buf. Then:

if numread, err := kon.Read(buf); err != nil {
    if val, ok := err.(os.Errno); ok {
        if val.Timeout() {
            println("Connection to:", kon.RemoteAddr().String(), "timed out.")
        }
    }
}

That's of course only a gist of the idea. In practice you probably want to do something more elegant (aka more RL complexleete) and consider more cases at once with Type switches.