+#ifndef S_IRWXU
+# define S_IRWXU (S_IRUSR|S_IWUSR|S_IXUSR)
+#endif
+
+#ifndef S_IRWXG
+# define S_IRWXG (S_IRGRP|S_IWGRP|S_IXGRP)
+#endif
+
+#ifndef S_IRWXO
+# define S_IRWXO (S_IROTH|S_IWOTH|S_IXOTH)
+#endif
+
+#ifndef S_IREAD
+# define S_IREAD S_IRUSR
+#endif
+
+#ifndef S_IWRITE
+# define S_IWRITE S_IWUSR
+#endif
+
+#ifndef S_IEXEC
+# define S_IEXEC S_IXUSR
+#endif
+