Comment 8 for bug 257217

OK, so lp:~mbp/bzr/257217-sighup catches sighup and turns it into an exception, and in toy tests this does indeed mean that we get a chance to unwind. However, in a more realistic test of closing the window while bzr's pushing to an sftp server, we get ERESTARTSYS from the send() syscall talking to the ssh child. We could of course fix that though I'm concerned it will send us back in to the mess of trying to handle that error that we recently had with SIGWINCH. (Specifically, iirc there are some bugs in python and libraries we use to do with restarting system calls.)