#define MAP_POPULATE 0x0040 /* populate (prefault) pagetables */
#define MAP_NONBLOCK 0x0080 /* do not block on IO */
#define MAP_GROWSDOWN 0x0100 /* stack-like segment */
+#define MAP_STACK MAP_GROWSDOWN /* provide convenience alias */
#define MAP_LOCKED 0x0200 /* pages are locked */
#define MAP_NORESERVE 0x0400 /* don't check for reservations */
#define MAP_DENYWRITE 0x0800 /* ETXTBSY */