use modern reboot
diff --git a/elksemu/elks_sys.c b/elksemu/elks_sys.c
index 5699edc..45c97f7 100644
--- a/elksemu/elks_sys.c
+++ b/elksemu/elks_sys.c
@@ -17,6 +17,8 @@
 #include <signal.h>
 #include <errno.h>
 #include <sys/types.h>
+#include <linux/reboot.h>
+#include <sys/reboot.h>
 #include <sys/resource.h>
 #include <sys/wait.h>
 #include <sys/ioctl.h>
@@ -656,11 +658,11 @@ static int elks_reboot(int bx,int cx,int dx,int di,int si)
    switch(dx)
    {
    /* graceful shutdown, C-A-D off, kill -? 1 */
-   case 0:     return reboot(0xfee1dead, 672274793, 0);
+   case 0:     return reboot(LINUX_REBOOT_CMD_CAD_OFF);
    /* Enable C-A-D */
-   case 0xCAD: return reboot(0xfee1dead, 672274793, 0x89abcdef);
+   case 0xCAD: return reboot(LINUX_REBOOT_CMD_CAD_ON);
    /* Time to die! */
-   case 0xD1E: return reboot(0xfee1dead, 672274793, 0x1234567);
+   case 0xD1E: return reboot(LINUX_REBOOT_CMD_RESTART);
    }
    return -1;
 }