Let players stop/start units:

(genitem, lndstr, nukstr, plnstr, shpstr): New members off, lnd_off,
nuk_off, pln_off, shp_off.
(NSC_GENITEM): New selector off.
(land, nuke, plan, shi): Display efficiency prefixed by `=' when off.
(start, stop, player_coms): Rewrite, new syntax.  Print only objects
that actually change.
(start_hdr, stop_hdr, start_stop_hdr): Consolidate.
(item_u, start_stop, start_stop_sector, proff, start_stop_unit)
(start_stop_unit_hdr, unit_type_name): New.
(upd_land, upd_plane, planerepair, upd_ship): Obey and clear stoppage.

include/genitem.h

@@ -50,6 +50,7 @@ struct genitem {
     signed char type;
     signed char effic;
     signed char mobil;
+    unsigned char off;
     short tech;
     char group;
     coord opx, opy;

include/land.h

@@ -57,6 +57,7 @@ struct lndstr {
     signed char lnd_type;	/* index in lchr[] */
     signed char lnd_effic;	/* 0% to 100% */
     signed char lnd_mobil;	/* mobility units */
+    unsigned char lnd_off;	/* repairs stopped? */
     short lnd_tech;		/* tech level ship was built at */
     char lnd_army;		/* group membership */
     coord lnd_opx, lnd_opy;	/* Op sector coords */

include/nuke.h

@@ -46,6 +46,7 @@ struct nukstr {
     signed char nuk_type;	/* index in plchr[] */
     signed char nuk_effic;	/* unused, always 100% */
     signed char nuk_mobil;	/* unused, always 0 */
+    unsigned char nuk_off;	/* repairs stopped? (unused) */
     short nuk_tech;		/* nuke's tech level */
     char nuk_stockpile;		/* group membership, unused */
     coord nuk_opx, nuk_opy;	/* Op sector coords, unused */

include/plane.h

@@ -42,10 +42,6 @@
 #define N_MAXPLANE	40
 #define	PLANE_MINEFF	10
 
-/*
- * some routines assume that from pln_x to pln_wing remains
- * exactly equivalent with shp_x to shp_fleet
- */
 struct plnstr {
     /* initial part must match struct genitem */
     short ef_type;
@@ -56,6 +52,7 @@ struct plnstr {
     signed char pln_type;	/* index in plchr[] */
     signed char pln_effic;	/* actually "training" */
     signed char pln_mobil;	/* plane mobility */
+    unsigned char pln_off;	/* repairs stopped? */
     short pln_tech;		/* plane's tech level */
     char pln_wing;		/* like fleet */
     coord pln_opx;		/* Op sector coords */

include/ship.h

@@ -69,6 +69,7 @@ struct shpstr {
     signed char shp_type;	/* index in mchr[] */
     signed char shp_effic;	/* 0% to 100% */
     signed char shp_mobil;	/* mobility units */
+    unsigned char shp_off;	/* repairs stopped? */
     short shp_tech;		/* tech level ship was built at */
     char shp_fleet;		/* group membership */
     coord shp_opx, shp_opy;	/* Op sector coords */