--- lunar.c.orig	Mon Aug 10 21:14:48 1992
+++ lunar.c	Tue Feb  4 01:04:18 1997
@@ -60,6 +60,10 @@
 #define	GanBM	4
 #define	ZhiBM	14
 
+#ifndef BITMAPFILE
+#define BITMAPFILE "lunar.bitmap"
+#endif
+
 typedef struct {
 int year, month, day, hour, weekday;
 int leap;	/* the lunar month is a leap month */
@@ -124,7 +128,7 @@
 
 int	showHZ = 0;			/* output in hanzi */
 int	showBM = 0;			/* output in bitmap */
-char	BMfile[] = "lunar.bitmap";	/* bit map file */
+char	BMfile[] = BITMAPFILE;	/* bit map file */
 char	GZBM[NBM][BMRow][BMCol];	/* the bitmap array */
 char	*progname;