prepare for c++17

code/1/1.1.cpp

@@ -0,0 +1,13 @@
+//
+// 1.1.cpp
+// c++1x tutorial
+//
+// created by changkun at shiyanlou.com
+//
+
+#include "foo.h"
+
+int main() {
+    add(1, 2);
+    return 0;
+}

code/1/Makefile

@@ -0,0 +1,6 @@
+TARGET = 1.1
+all:
+	gcc -c foo.c
+	g++ 1.1.cpp foo.o -o $(TARGET)
+clean:
+	rm -rf *.o $(TARGET)

code/1/foo.c

@@ -0,0 +1,13 @@
+//
+// foo.c
+// c++1x tutorial
+//
+// created by changkun at shiyanlou.com
+//
+
+
+#include "foo.h"
+
+int add(int x, int y) {
+    return x+y;
+}

code/1/foo.h

@@ -0,0 +1,17 @@
+//
+// foo.h
+// c++1x tutorial
+//
+// created by changkun at shiyanlou.com
+//
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+    
+int add(int x, int y);
+    
+#ifdef __cplusplus
+}
+#endif