Microsoft® Windows® Script Interfaces
 Language Reference

HRESULT GetDocVersionString(
    BSTR *pbstrVersionString  // address of document version string

Retrieves a host-defined string that uniquely identifies the current document version. If the related document has changed outside the scope of Windows Script (as in the case of an HTML page being edited with NotePad), the scripting engine can save this along with its persisted state, forcing a recompile the next time the script is loaded.

[out] Address of the host-defined document version string.

If E_NOTIMPL is returned, the scripting engine should assume that the script is in sync with the document.