How to Add a Mob Flag

Index: fight.c
===================================================================
--- fight.c     (revision 197)
+++ fight.c     (working copy)
@@ -682,8 +682,9 @@
     return (0);
   }

-  /* shopkeeper protection */
-  if (!ok_damage_shopkeeper(ch, victim))
+  /* shopkeeper and MOB_NOKILL protection */
+  if (!ok_damage_shopkeeper(ch, victim) || MOB_FLAGGED(victim, MOB_NOKILL)) {
+    send_to_char(ch, "This mob is protected.\r\n");
     return (0);
+  }

   /* You can't damage an immortal! */
Index: structs.h
===================================================================
--- structs.h   (revision 197)
+++ structs.h   (working copy)
@@ -181,44 +181,44 @@
 #define MOB_NOSUMMON       14   /**< Mob can't be summoned */
 #define MOB_NOSLEEP        15   /**< Mob can't be slept */
-#define MOB_NOBASH         16   /**< Mob can't be bashed (e.g. trees) */
+#define MOB_NOKILL         16   /**< Mob can't be bashed (e.g. trees) */
 #define MOB_NOBLIND        17   /**< Mob can't be blinded */
 #define MOB_NOTDEADYET     18   /**< (R) Mob being extracted */
 /** Total number of Mob Flags; it should be 1 less than MOB_NOT_DEADYET */
Index: constants.c
===================================================================
--- constants.c (revision 197)
+++ constants.c (working copy)
@@ -187,7 +187,7 @@
   "NO_CHARM",
   "NO_SUMMN",
   "NO_SLEEP",
-  "NO_BASH",
+  "NO_KILL",
   "NO_BLIND",
   "DEAD",    /* You should never see this. */
   "\n"
Index: spell_parser.c
===================================================================
--- spell_parser.c      (revision 200)
+++ spell_parser.c      (working copy)
@@ -212,6 +212,10 @@
     act("White light from no particular source suddenly fills the room, then va
nishes.", FALSE, caster, 0, 0, TO_ROOM);
     return (0);
   }
+  if (cvict && MOB_FLAGGED(cvict, MOB_NOKILL)) {
+    send_to_char(caster, "This mob is protected.\r\n");
+    return (0);
+  }
   /* determine the type of saving throw */
   switch (casttype) {
   case CAST_STAFF:
Index: act.offensive.c
===================================================================
--- act.offensive.c     (revision 197)
+++ act.offensive.c     (working copy)
@@ -294,12 +294,13 @@
     send_to_char(ch, "Aren't we funny today...\r\n");
     return;
   }
+  if (MOB_FLAGGED(vict, MOB_NOKILL)) {
+    send_to_char(ch, "This mob is protected.\r\n");
+    return;
+  }
   percent = rand_number(1, 101);       /* 101% is a complete failure */
   prob = GET_SKILL(ch, SKILL_BASH);

-  if (MOB_FLAGGED(vict, MOB_NOBASH))
-    percent = 101;
-
   if (percent > prob) {
     damage(ch, vict, 0, SKILL_BASH);
     GET_POS(ch) = POS_SITTING;