https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=251868
This patch is for adding the tcgetwinsize() and tcsetwinsize() functions that are now available in NetBSD and are expected to be a part of POSIX.1 issue 8. These functions get/set tty winsize respectively. Please see https://www.austingroupbugs.net/view.php?id=1151#c3856.
If this patch is accepted, then
1. please use "soumendraganguly AT gmail DOTCOM" for my email address in the commit;
2. I will happily create documentation for tcgetwinsize(), tcsetwinsize()!