--- Gnu-Mach/i386/i386at/cram.h	2020/09/02 04:36:58	1.1.1.1
+++ Gnu-Mach/i386/i386at/cram.h	2020/09/02 04:49:19	1.1.1.2
@@ -50,6 +50,9 @@ NEGLIGENCE, OR OTHER TORTIOUS ACTION, AR
 WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
 
+#ifndef _CRAM_H_
+#define _CRAM_H_
+
 /* 
  * outb(CMOS_ADDR, addr);
  * result = inb(CMOS_DATA);
@@ -73,3 +76,4 @@ WITH THE USE OR PERFORMANCE OF THIS SOFT
 #define CM_CGA_80	0x20
 #define CM_MONO_80	0x30
 
+#endif /* _CRAM_H_ */