Add ctrlaltdel tool

Makefile

@@ -20,6 +20,7 @@ LIB = \
 SRC = \
 	chvt.c              \
 	clear.c             \
+	ctrlaltdel.c        \
 	df.c                \
 	dmesg.c             \
 	eject.c             \

ctrlaltdel.c

@@ -0,0 +1,43 @@
+/* See LICENSE file for copyright and license details. */
+#include <sys/syscall.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "reboot.h"
+#include "util.h"
+
+static void
+usage(void)
+{
+	eprintf("usage: %s [-hs]\n", argv0);
+}
+
+int
+main(int argc, char *argv[])
+{
+	int hflag = 0;
+	int sflag = 0;
+	int cmd;
+
+	ARGBEGIN {
+	case 'h':
+		hflag = 1;
+		break;
+	case 's':
+		sflag = 1;
+		break;
+	default:
+		usage();
+	} ARGEND;
+
+	if (argc > 0 || (hflag != 0 && sflag != 0) ||
+	    (hflag == 0 && sflag == 0))
+		usage();
+
+	cmd = hflag ? LINUX_REBOOT_CMD_CAD_ON : LINUX_REBOOT_CMD_CAD_OFF;
+
+	if (syscall(__NR_reboot, LINUX_REBOOT_MAGIC1,
+		    LINUX_REBOOT_MAGIC2, cmd, NULL) < 0)
+		eprintf("reboot:");
+	return EXIT_SUCCESS;
+}