Inside Macintosh: Files
This section describes the high-level volume access routines. Unless your application has very specialized needs, you should be able to manage all volume access using the routines described in this section. In fact, most applications are likely to need only the FlushVol function described in the next section, "Updating Volumes."
When you call one of these routines, you specify a volume by a volume reference number (which you can obtain, for example, by calling the GetVInfo function, or from the reply record returned by the Standard File Package). You can also specify a volume by name, but this is generally discouraged, because there is no guarantee that volume names are unique.