Path: utzoo!mnetor!uunet!husc6!bbn!uwmcsd1!ig!agate!garnet.berkeley.edu!csaron From: csaron@garnet.berkeley.edu (Aron Roberts) Newsgroups: comp.sys.mac.hypercard Subject: HyperCard 1.1 and locked disks or volumes Message-ID: <7969@agate.BERKELEY.EDU> Date: 24 Mar 88 17:46:49 GMT Sender: usenet@agate.BERKELEY.EDU Reply-To: csaron@garnet.berkeley.edu (Aron Roberts) Organization: University of California, Berkeley Lines: 62 Keywords: locked disks volumes debug writeoff writeon scripting As has been noted previously in this newsgroup, HyperCard 1.1 can now run off of, and use stacks which are located on, a *locked* file, disk, or network volume. This has particular utility in settings with one or more file servers, for it now allows many users to simultaneously share stacks which are stored on a read-only volume on the file server, without first having to copy these stacks to their own local disk storage. It also allows the current version of HyperCard to immediately begin making use of stacks located on CD-ROM, which is apparently the primary purpose of this added functionality in version 1.1. ** The method described below is a temporary hack which will be ** removed in subsequent versions of HyperCard. Use at your own risk. The command "debug writeoff" allows HyperCard to use stacks on locked volumes by turning off the automatic saving feature of the program. Any changes made to stacks will be made only in memory, and these changes will not be present when the stack is exited and reentered. One can still use the "Save a Copy ..." command from HyperCard's file menu, but this command will only create a duplicate stack which mirrors the initial state of the stack one is working in; it will not save any changes which have been made. The command "debug writeon" turns on automatic saving of changes, and thus restores HyperCard's default state in this regard. Both of these "debug" commands can be typed into the message box or incorporated into scripts in the same manner as other HyperTalk commands. David Leffler of Apple has confirmed in a recent communication that "The Home stack must be on an unlocked volume ..." As a result, an appropriate place for the "debug writeoff" command is in the "on startup" handler in the Home stack. If a Home stack which has been modified in this way is launched directly from an unlocked disk or volume, the HyperCard application itself and all other stacks which are to be accessed by HyperCard can be located on locked disks or volumes. Stacks can be accessed in any privileges mode otherwise permitted, from Browsing through Scripting, since changes to stacks on locked volumes are not permanent. According to Apple's HyperCard product manager Mike Holm, quoted by Rory J. O'Connor in the article "CD-ROM eludes HyperCard" (Macintosh Today, 22 March 1988, p. 7), the "debug writeoff" command in HyperCard 1.1 is "temporary in the extreme, a hack in the true sense of the word. It will be removed when the new version is released." The article states that Apple has been working since December 1987 on a version of HyperCard which will officially support locked volumes, and particularly Apple's forthcoming CD-ROM product, now scheduled to ship in May 1988. A prototype of this new version of HyperCard is expected to be sent to developers in early April. According to Holm, "The next version will read a disk that's on CD-ROM, or a locked disk or a file that's locked under the Finder. It'll tell you you can't make changes, and the plan right now is to avoid a lot of alerts, bells and whistles." Aron Roberts Tolman Microcomputer Facility 1535 Tolman Hall, University of California Berkeley, CA 94720 (415) 642-2251 csaron@garnet.Berkeley.EDU CSARON@UCBCMSA.BITNET