Unfortunately this area is not standardized by POSIX. Linux uses an ioctl
which is not that bad, but I'd like to have a designated function. I'm not
sure if this facility is powerful enough and whether it should be improved.
Also note that I use a struct winsize as on Linux, but I use size_ts instead
for the heck of it. Perhaps I should use another name for the struct.
This will allow development of a better terminal providing stdin.
Added new system calls settermmode(2) and gettermmode(2) declared in
<sys/termmode.h>. They allow querying and changing the current mode of
terminals (enabling raw keyboard data, signal handling, line buffering,
UTF-8 encoding stdin, and more). However, all that is unsupported by the
current terminal device driver.
Added KBKEY_ENCODE and KBKEY_DECODE macros to <sys/keycodes.h> which allows
encoding the kbkey format in UTF-32 characters.
