Remove limitation

[pwillemse]

When trying to send snmp messages I discovered that jython was hanging when sending messages > 64k. In jython 2.7.0 it worked fine. In _socket.py a limitation on the message size was found. Why just truncating a message and not handling the rest of the message? After removal it worked fine.

[Stewori]

For me this looks like self.channel.bytesBeforeUnwritable() returns a too restrictive value. I suspect that bytesBeforeUnwritable() does not exist for nothing, maybe a better solution would be to fix it. However, I'm no expert in this area and must admit the I actually don't know what bytesBeforeUnwritable() is about and what consequences it can have to ignore it.

[pwillemse]

Why was this code not present in jython 2.7.0 and added in 2.7.1? Was this only because some one was worried about the size of the packets? See FIXME label in the code
One thing for sure: SNMP is broken when sending packets > 64k.

[jeff5]

The change that added this (b348d77 and #45) is offered as a fix for http://bugs.jython.org/issue2508, and the present PR essentially reverts the code change in that fix, re-opening the bug. This may be an improvement, but it isn't going to provide correct behaviour.

It was pointed out later that the code change in #45 has introduced another problem http://bugs.jython.org/issue2618, which I guess is what the OP is struggling with. @Stewori : I'd say bytesBeforeUnwritable exists for a reason, but perhaps not the one we're using it for here.

@jimbaker : Is it possible we are providing non-blocking semantics in circumstances where an application really needs the library to block?

[jeff5]

Unfortunately a PR (unlike an issue) cannot be transferred to the new official home at https://github.com/jython/jython. Keeping this open in the frozen-mirror to allow for further consideration.