diff --git a/ndhc/clientpacket.h b/ndhc/clientpacket.h
index 089bf36..a0a3b4e 100644
--- a/ndhc/clientpacket.h
+++ b/ndhc/clientpacket.h
@@ -1,5 +1,5 @@
-#ifndef _CLIENTPACKET_H
-#define _CLIENTPACKET_H
+#ifndef CLIENTPACKET_H_
+#define CLIENTPACKET_H_
 
 #include <stdint.h>
 
diff --git a/ndhc/dhcpc.h b/ndhc/dhcpc.h
index 1a7e81f..0d4e9f3 100644
--- a/ndhc/dhcpc.h
+++ b/ndhc/dhcpc.h
@@ -1,5 +1,5 @@
-#ifndef _DHCPC_H
-#define _DHCPC_H
+#ifndef DHCPC_H_
+#define DHCPC_H_
 
 enum {
 	INIT_SELECTING,
diff --git a/ndhc/options.h b/ndhc/options.h
index 48ec426..9def838 100644
--- a/ndhc/options.h
+++ b/ndhc/options.h
@@ -1,6 +1,6 @@
 /* options.h */
-#ifndef _OPTIONS_H
-#define _OPTIONS_H
+#ifndef OPTIONS_H_
+#define OPTIONS_H_
 
 #include "packet.h"
 
@@ -35,6 +35,5 @@ int end_option(unsigned char *optionptr);
 int add_option_string(unsigned char *optionptr, unsigned char *string);
 int add_simple_option(unsigned char *optionptr, unsigned char code, uint32_t data);
 struct option_set *find_option(struct option_set *opt_list, char code);
-/* void attach_option(struct option_set **opt_list, struct dhcp_option *option, char *buffer, int length); */
 
 #endif
diff --git a/ndhc/packet.h b/ndhc/packet.h
index 45e500f..3e88bdf 100644
--- a/ndhc/packet.h
+++ b/ndhc/packet.h
@@ -1,5 +1,5 @@
-#ifndef _PACKET_H
-#define _PACKET_H
+#ifndef PACKET_H_
+#define PACKET_H_
 
 #include <netinet/udp.h>
 #include <netinet/ip.h>
@@ -20,7 +20,7 @@ struct dhcpMessage {
 	uint8_t sname[64];
 	uint8_t file[128];
 	uint32_t cookie;
-	uint8_t options[308]; /* 312 - cookie */ 
+	uint8_t options[308]; /* 312 - cookie */
 };
 
 struct udp_dhcp_packet {
diff --git a/ndhc/script.h b/ndhc/script.h
index 7bbaa77..2cf7b97 100644
--- a/ndhc/script.h
+++ b/ndhc/script.h
@@ -1,5 +1,5 @@
-#ifndef _SCRIPT_H
-#define _SCRIPT_H
+#ifndef SCRIPT_H_
+#define SCRIPT_H_
 
 enum {
 	SCRIPT_DECONFIG = 0,
diff --git a/ndhc/socket.h b/ndhc/socket.h
index fec361a..e8090d6 100644
--- a/ndhc/socket.h
+++ b/ndhc/socket.h
@@ -1,6 +1,6 @@
 /* socket.h */
-#ifndef _SOCKET_H
-#define _SOCKET_H
+#ifndef SOCKET_H_
+#define SOCKET_H_
 
 int read_interface(char *interface, int *ifindex, uint32_t *addr, unsigned char *arp);
 int listen_socket(unsigned int ip, int port, char *inf);