Review interface of fileio.

estruct.h

@@ -256,10 +256,18 @@
 #undef	TRUE
 #endif
 
+#if 0
 #define FALSE   0		/* False, no, bad, etc.         */
 #define TRUE    1		/* True, yes, good, etc.        */
 #define ABORT   2		/* Death, ^G, abort, etc.       */
 #define	FAILED	3		/* not-quite fatal false return */
+#endif
+typedef enum {
+	FALSE,
+	TRUE
+} boolean ;
+
+#define ABORT 2
 
 #define	STOP	0		/* keyboard macro not in use    */
 #define	PLAY	1		/*                playing       */