diff --git a/include/prototypes.h b/include/prototypes.h
index 07a03b64..13c0ed7c 100644
--- a/include/prototypes.h
+++ b/include/prototypes.h
@@ -363,6 +363,7 @@ extern int natpass(natid, char *);
 extern struct player *player;	/* current player's context */
 extern char *praddr(struct player *);
 extern void player_main(struct player *);
+extern void make_stale_if_command_arg(char *);
 /* more under Commands */
 /* recvclient.c */
 extern int recvclient(char *, int);
diff --git a/src/lib/player/player.c b/src/lib/player/player.c
index 7f40b13e..d93211eb 100644
--- a/src/lib/player/player.c
+++ b/src/lib/player/player.c
@@ -202,6 +202,36 @@ status(void)
     return 1;
 }
 
+/* Is ARG one of the player's last command's arguments?  */
+static int
+is_command_arg(char *arg)
+{
+    int i;
+
+    for (i = 1; i < 128 && player->argp[i]; i++) {
+	if (arg == player->argp[i])
+	    return 1;
+    }
+    return 0;
+}
+
+/*
+ * Make all objects stale if ARG is one of the player's command arguments.
+ * See ef_make_stale() for what "making stale" means.
+ * Useful for functions that prompt for missing arguments.
+ * These can yield the processor, so we'd like to call ef_make_stale()
+ * there.  Except that leads to false positives when the caller passes
+ * an argument that is never null, and relies on the fact that the
+ * function doesn't yield then.  We can't know that in general.  But
+ * we do know in the common special case of command arguments.
+ */
+void
+make_stale_if_command_arg(char *arg)
+{
+    if (is_command_arg(arg))
+	ef_make_stale();
+}
+
 /*
  * XXX This whole mess should be redone; execute block should
  * start with "exec start", and should end with "exec end".
diff --git a/src/lib/subs/getstarg.c b/src/lib/subs/getstarg.c
index 20c6af61..731bed1e 100644
--- a/src/lib/subs/getstarg.c
+++ b/src/lib/subs/getstarg.c
@@ -34,6 +34,7 @@
 
 #include <string.h>
 #include "misc.h"
+#include "prototypes.h"
 
 /*
  * Get string argument.
@@ -50,6 +51,7 @@ getstarg(char *input, char *prompt, char *buf)
 	    return NULL;
     } else {
 	strcpy(buf, input);
+	make_stale_if_command_arg(input);
     }
     return buf;
 }
diff --git a/src/lib/subs/onearg.c b/src/lib/subs/onearg.c
index b97ce0a7..3784bdc7 100644
--- a/src/lib/subs/onearg.c
+++ b/src/lib/subs/onearg.c
@@ -43,7 +43,8 @@ onearg(char *arg, char *prompt)
     if (!arg || !*arg) {
 	if (!(arg = getstring(prompt, buf)))
 	    return -1;
-    }
+    } else
+	make_stale_if_command_arg(arg);
     n = atoi(arg);
     if (n < 0)
 	return -1;
diff --git a/src/lib/subs/snxtitem.c b/src/lib/subs/snxtitem.c
index da8b86ad..bcb8f7d0 100644
--- a/src/lib/subs/snxtitem.c
+++ b/src/lib/subs/snxtitem.c
@@ -73,9 +73,9 @@ snxtitem(struct nstr_item *np, int type, char *str, char *prompt)
 	str = getstring(prompt, buf);
 	if (!str)
 	    return 0;
-    }
+    } else
+	make_stale_if_command_arg(str);
     if (*str == 0) {
-	/* empty string passed by player */
 	return 0;
     }
     if (type == EF_NATION && isalpha(*str)) {
diff --git a/src/lib/subs/snxtsct.c b/src/lib/subs/snxtsct.c
index 7657c456..01d8b597 100644
--- a/src/lib/subs/snxtsct.c
+++ b/src/lib/subs/snxtsct.c
@@ -44,7 +44,7 @@
 
 /*
  * setup the nstr_sect structure for sector selection.
- * can select on either NS_ALL, NS_AREA, or NS_RANGE
+ * can select on either NS_ALL, NS_AREA, or NS_DIST
  * iterate thru the "condarg" string looking
  * for arguments to compile into the nstr.
  * Using this function for anything but command arguments is usually
@@ -63,7 +63,8 @@ snxtsct(struct nstr_sect *np, char *str)
     if (!str || !*str) {
 	if (!(str = getstring("(sects)? ", buf)))
 	    return 0;
-    }
+    } else
+	make_stale_if_command_arg(str);
     switch (sarg_type(str)) {
     case NS_AREA:
 	if (!sarg_area(str, &range))