Function cngetc

freebsd/kern/kern_cons.c:414–426

* Low level console routines. */

 * Low level console routines.
 */
int
cngetc(void)
{
	int c;

	if (cn_mute)
		return (-1);
	while ((c = cncheckc()) == -1)
		cpu_spinwait();
	if (c == '\r')
		c = '\n';		/* console input is always ICRNL */
	return (c);
}

int
cncheckc(void)