+/**
+ * EXPERIMENTAL, since wimlib v1.9.0: create a temporary filesystem snapshot of
+ * the source directory and add the files from it. Currently, this option is
+ * only supported on Windows (Vista and later), where it uses the Volume Shadow
+ * Copy Service (VSS). Using this option, you can create a consistent backup of
+ * the system volume of a running Windows system without running into problems
+ * with locked files. For the VSS snapshot to be successfully created, your
+ * application must be run as an Administrator, and it cannot be run in WoW64
+ * mode (i.e. if Windows is 64-bit, then your application must be 64-bit as
+ * well).
+ */
+#define WIMLIB_ADD_FLAG_SNAPSHOT 0x00008000
+