One implication of storing the file handle is that the handle and MFS information stored in the FILES file must be updated if anything about a file changes that would normally affect the file handle.
A common example is the addition or removal of an MFS to a file. If an MFS is added to a file, the entry in the FILES file must reflect this change. The FILES file is write-protected. As a result, changes to the file handle must be registered indirectly. In essence, the programmer must force the system to clear the file handle in the FILES file, and thereby guarantee that the BASIC+ interpreter generate an OPEN.FILE call to the filing system the next time the file is accessed.
To do so, the programmer should detach and then re-attach the file after making appropriate changes such as installing the MFS.
