* If the client was unable to write any data, write would return -1 with
errno==EAGAIN, and the client would assert fail.
* Apparently I thought that continue would jump to the start of the
do-while(0) loop. Replace the continue/do-while(0) with a
did_something flag.
While I'm at it, replace a few hard-coded constants with constants.
handled.
Use the UnixSignalHandler to detect terminal resizing. The client doesn't
do anything with the terminal size yet. It should send the size to the
server.
