This should avoid the possibility of the SIGWINCH handler's blocking
when trying to write to the pipe. This could only happen if we'd
somehow received PIPE_BUF SIGWINCHes without reading the pipe, which
would be difficult to achieve.
While we're at it, also set O_NONBLOCK on the reading side of the pipe,
just in case.
perror("pipe");
exit(1);
}
+ /* We don't want the signal handler to block if the pipe's full. */
+ nonblock(signalpipe[0]);
+ nonblock(signalpipe[1]);
putty_signal(SIGWINCH, sigwinch);
/*