diff --git a/s/preview b/s/preview
index b22b34e76..ff3a7c1ee 100755
--- a/s/preview
+++ b/s/preview
@@ -22,8 +22,8 @@ exit $2 # otherwise
 function build() {
 assert_dir $SOURCE
 cd $SOURCE
-git pull || abort "failed to update source. do you have local changes?"
 [ -z $1 ] || git checkout $1
+git pull || abort "failed to update source. do you have local changes?"
 s/build || abort "build failed."
 }
 
diff --git a/src/economy.c b/src/economy.c
index 86fb14a3d..9899b8c58 100644
--- a/src/economy.c
+++ b/src/economy.c
@@ -1823,7 +1823,8 @@ int make_cmd(unit * u, struct order *ord)
             cmistake(u, ord, 275, MSG_PRODUCE);
         }
         else {
-            direction_t d = get_direction(getstrtoken(), u->faction->locale);
+            const char * s = getstrtoken();
+            direction_t d = s ? get_direction(s, u->faction->locale) : NODIRECTION;
             if (d != NODIRECTION) {
                 build_road(r, u, m, d);
             }
@@ -2060,6 +2061,8 @@ static void buy(unit * u, request ** buyorders, struct order *ord)
     attrib *a;
     const item_type *itype = NULL;
     const luxury_type *ltype = NULL;
+    const char *s;
+
     if (u->ship && is_guarded(r, u, GUARD_CREWS)) {
         cmistake(u, ord, 69, MSG_INCOME);
         return;
@@ -2134,7 +2137,8 @@ static void buy(unit * u, request ** buyorders, struct order *ord)
     /* die Menge der verkauften Güter merken */
     a->data.i += n;
 
-    itype = finditemtype(getstrtoken(), u->faction->locale);
+    s = getstrtoken();
+    itype = s ? finditemtype(s, u->faction->locale) : 0;
     if (itype != NULL) {
         ltype = resource2luxury(itype->rtype);
         if (ltype == NULL) {
diff --git a/src/items.c b/src/items.c
index 2a4c81568..8292c4ebe 100644
--- a/src/items.c
+++ b/src/items.c
@@ -32,39 +32,48 @@
 #define MAXGAIN 15
 static int
 use_studypotion(struct unit *u, const struct item_type *itype, int amount,
-  struct order *ord)
-{
-  if (getkeyword(u->thisorder) == K_STUDY) {
-    skill_t sk;
-    skill *sv;
-
-    init_tokens(u->thisorder);
-    skip_token();
-    sk = get_skill(getstrtoken(), u->faction->locale);
-    sv = unit_skill(u, sk);
-
-    if (sv && sv->level > 2) {
-      /* TODO: message */
-    } else if (study_cost(u, sk) > 0) {
-      /* TODO: message */
-    } else {
-      attrib *a = a_find(u->attribs, &at_learning);
-      teaching_info *teach;
-      if (a == NULL) {
-        a = a_add(&u->attribs, a_new(&at_learning));
-      }
-      teach = (teaching_info *) a->data.v;
-      if (amount > MAXGAIN)
-        amount = MAXGAIN;
-      teach->value += amount * 30;
-      if (teach->value > MAXGAIN * 30) {
-        teach->value = MAXGAIN * 30;
-      }
-      i_change(&u->items, itype, -amount);
-      return 0;
+                struct order *ord)
+{   
+    if (getkeyword(u->thisorder) == K_STUDY) {
+        skill_t sk = NOSKILL;
+        skill *sv = 0;
+        const char * s = getstrtoken();
+        attrib *a;
+        teaching_info *teach;
+        
+        init_tokens(u->thisorder);
+        skip_token();
+        if (s) {
+            sk = get_skill(s, u->faction->locale);
+            sv = unit_skill(u, sk);
+        }
+        if (sv) {
+            if (sv->level > 2) {
+                /* TODO: message */
+                return EUNUSABLE;
+            } else if (study_cost(u, sk) > 0) {
+                /* TODO: message */
+                return EUNUSABLE;
+            }
+        }
+        
+        a = a_find(u->attribs, &at_learning);
+        if (a == NULL) {
+            a = a_add(&u->attribs, a_new(&at_learning));
+        }
+        
+        teach = (teaching_info *) a->data.v;
+        if (amount > MAXGAIN) {
+            amount = MAXGAIN;
+        }
+        teach->value += amount * 30;
+        if (teach->value > MAXGAIN * 30) {
+            teach->value = MAXGAIN * 30;
+        }
+        i_change(&u->items, itype, -amount);
+        return 0;
     }
-  }
-  return EUNUSABLE;
+    return EUNUSABLE;
 }
 
 /* END studypotion */
diff --git a/src/kernel/build.c b/src/kernel/build.c
index 0763cbe16..575500b3d 100644
--- a/src/kernel/build.c
+++ b/src/kernel/build.c
@@ -90,47 +90,49 @@ ship *getship(const struct region * r)
 
 static void destroy_road(unit * u, int nmax, struct order *ord)
 {
-  direction_t d = get_direction(getstrtoken(), u->faction->locale);
-  unit *u2;
-  region *r = u->region;
-  short n = (short)nmax;
+    const char *s = getstrtoken();
+    direction_t d = s ? get_direction(s, u->faction->locale) : NODIRECTION;
+    if (d == NODIRECTION) {
+        /* Die Richtung wurde nicht erkannt */
+        cmistake(u, ord, 71, MSG_PRODUCE);
+    } else {
+        unit *u2;
+        region *r = u->region;
+        short road, n = (short)nmax;
+        
+        if (nmax > SHRT_MAX) {
+            n = SHRT_MAX;
+        } else if (nmax < 0) {
+            n = 0;
+        }
 
-  if (nmax > SHRT_MAX)
-    n = SHRT_MAX;
-  else if (nmax < 0)
-    n = 0;
+        for (u2 = r->units; u2; u2 = u2->next) {
+            if (u2->faction != u->faction && is_guard(u2, GUARD_TAX)
+                && cansee(u2->faction, u->region, u, 0)
+                && !alliedunit(u, u2->faction, HELP_GUARD)) {
+                cmistake(u, ord, 70, MSG_EVENT);
+                return;
+            }
+        }
 
-  for (u2 = r->units; u2; u2 = u2->next) {
-    if (u2->faction != u->faction && is_guard(u2, GUARD_TAX)
-      && cansee(u2->faction, u->region, u, 0)
-      && !alliedunit(u, u2->faction, HELP_GUARD)) {
-      cmistake(u, ord, 70, MSG_EVENT);
-      return;
+        road = rroad(r, d);
+        n = _min(n, road);
+        if (n != 0) {
+            region *r2 = rconnect(r, d);
+            int willdo = eff_skill(u, SK_ROAD_BUILDING, r) * u->number;
+            willdo = _min(willdo, n);
+            if (willdo == 0) {
+                /* TODO: error message */
+            }
+            if (willdo > SHRT_MAX)
+              road = 0;
+            else
+              road = road - (short)willdo;
+            rsetroad(r, d, road);
+            ADDMSG(&u->faction->msgs, msg_message("destroy_road",
+                                                  "unit from to", u, r, r2));
+        }
     }
-  }
-
-  if (d == NODIRECTION) {
-    /* Die Richtung wurde nicht erkannt */
-    cmistake(u, ord, 71, MSG_PRODUCE);
-  } else {
-    short road = rroad(r, d);
-    n = _min(n, road);
-    if (n != 0) {
-      region *r2 = rconnect(r, d);
-      int willdo = eff_skill(u, SK_ROAD_BUILDING, r) * u->number;
-      willdo = _min(willdo, n);
-      if (willdo == 0) {
-        /* TODO: error message */
-      }
-      if (willdo > SHRT_MAX)
-        road = 0;
-      else
-        road = road - (short)willdo;
-      rsetroad(r, d, road);
-      ADDMSG(&u->faction->msgs, msg_message("destroy_road",
-          "unit from to", u, r, r2));
-    }
-  }
 }
 
 int destroy_cmd(unit * u, struct order *ord)
diff --git a/src/kernel/config.c b/src/kernel/config.c
index 5fe492633..435c78dca 100644
--- a/src/kernel/config.c
+++ b/src/kernel/config.c
@@ -1142,7 +1142,8 @@ unsigned int getuint(void)
 
 int getint(void)
 {
-    return atoi((const char *)getstrtoken());
+    const char * s = getstrtoken();
+    return s ? atoi(s) : 0;
 }
 
 const struct race *findrace(const char *s, const struct locale *lang)
@@ -1213,7 +1214,8 @@ bool isparam(const char *s, const struct locale * lang, param_t param)
 
 param_t getparam(const struct locale * lang)
 {
-    return findparam(getstrtoken(), lang);
+    const char *s = getstrtoken();
+    return s ? findparam(s, lang) : NOPARAM;
 }
 
 faction *findfaction(int n)
diff --git a/src/laws.c b/src/laws.c
index 34f8ca08b..27c28a67e 100755
--- a/src/laws.c
+++ b/src/laws.c
@@ -2359,9 +2359,10 @@ int banner_cmd(unit * u, struct order *ord)
 {
     init_tokens(ord);
     skip_token();
+    const char * s = getstrtoken();
 
     free(u->faction->banner);
-    u->faction->banner = _strdup(getstrtoken());
+    u->faction->banner = s ? _strdup(s) : 0;
     add_message(&u->faction->msgs, msg_message("changebanner", "value",
         u->faction->banner));
 
diff --git a/src/study.c b/src/study.c
index 28fe9f9e3..ecff06624 100644
--- a/src/study.c
+++ b/src/study.c
@@ -59,7 +59,8 @@ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
 static skill_t getskill(const struct locale *lang)
 {
-    return get_skill(getstrtoken(), lang);
+    const char * s = getstrtoken();
+    return s ? get_skill(s, lang) : NOSKILL;
 }
 
 magic_t getmagicskill(const struct locale * lang)