Create ZERO_VAR and ZERO_ARRAY convenience macros

(getting tired of typing "memset(var,0,sizeof(var))").

src/xpdev/gen_defs.h

@@ -217,6 +217,10 @@ typedef struct {
 #define SKIP_HEXDIGIT(p)			while(*(p) && isxdigit(*(p)))			(p)++;
 #define FIND_HEXDIGIT(p)			while(*(p) && !isxdigit(*(p)))			(p)++;
 
+/* Variable/buffer initialization (with zeros) */
+#define ZERO_VAR(var)				memset(&var,0,sizeof(var))
+#define ZERO_ARRAY(array)			memset(array,0,sizeof(array))
+
 /****************************************************************************/
 /* MALLOC/FREE Macros for various compilers and environments				*/
 /* MALLOC is used for allocations of 64k or less							*/