--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/unionTest/unionTest.c	Fri Mar 12 18:45:11 2021 +0900
@@ -0,0 +1,26 @@
+#include <stdio.h>
+
+typedef struct hoge {
+  int foo;
+  char* bar;
+} hoge;
+
+typedef struct hoge2 {
+  int foo;  
+  char* bar;
+} hoge2;
+
+union UNION{
+  struct hoge hoge;
+  struct hoge2 hoge2;  
+};
+
+int main () {
+  hoge hu = {11, "hello"};
+  union UNION *unionTest = (union UNION*) &hu;
+  //printf("%d\n", unionTest->hoge.foo);
+  printf("%d\n", ((hoge*)unionTest)->foo);
+  return 0;
+}
+
+