diff --git a/bin/Makefile b/bin/Makefile
index 07d65de..2d773a7 100644
--- a/bin/Makefile
+++ b/bin/Makefile
@@ -7,6 +7,9 @@ OS := LINUX
 #OS := MACOS
 export OS
 
+# Data path.
+#DATA_DEF := "ldata"
+
 #CC = clang
 
 # VERSION.
diff --git a/src/lephisto.h b/src/lephisto.h
index 661643b..058beb3 100644
--- a/src/lephisto.h
+++ b/src/lephisto.h
@@ -19,7 +19,9 @@
 
 #define pow2(x)  ((x)*(x))              /**< ^2 */
 
-#define DATA_DEF    "ldata"              /**< Default data packfile. */
+#ifndef DATA_DEF
+#define DATA_DEF   "ldata"              /**< Default data packfile. */
+#endif
 extern char* data;                      /**< Modifiable datafile. */
 #define DATA        data                /**< Standard data file to use. */
 #define DATA_NAME_LEN 32                /**< Max length of data name. */