old_tc
(void) tcgetattr(0, &old_tc);
new_tc = old_tc;
(void) memcpy(new_tc.c_cc, old_tc.c_cc, sizeof (old_tc.c_cc));
tmp_tc.c_cflag |= old_tc.c_cflag & (CSIZE|PARENB);
tmp_tc = old_tc;
out = cfgetospeed(&old_tc);
in = cfgetispeed(&old_tc);
static struct termio old_tc = { 0 };