This program is in the form of an INIT, which means that it is automatically executed by the System when your machine starts up.
This INIT allows switching between Systems 5, 6 and 7 without having to boot off a floppy or whatever. It is useful for switching between Systems to avoid compatibility problems, e.g. to run an old application which is incompatible with System 7 under System 6. Please read the comments under Installation, below, for more information.
Compatibility
This INIT should work on all Macintoshes, especially the Plus and above. However, you are warned that several users have had problems with this INIT, including myself. I no longer support it, but since many users reported no problems with it and find it useful, I am not withdrawing it from availability. Use at your own risk.
Note that you really need a hard disk for this INIT to be of use, as you can’t practically fit two different System and Finder files on a single floppy disk. In any case, floppy users can simply boot up with different disks, so they don’t need this INIT.
Installation
To install, simply drag the 5-6-7 INIT icon into your System folder. The next time you restart or turn your machine on, it will be available. That’s the easy part. As it is, the INIT will not do anything at all, except display its icon when you start up to show it is there. In order to actually be able to switch between Systems, you have to do a bit of work. Firstly, you need to have a different version of the System and Finder from the one you use normally (so you’ve got something to switch to). Note that you cannot (easily) use two different Systems previous to System release 6.0, as the earlier ones lack the ‘vers’ ID 1 resource necessary to switch. (Hackers can add or modify this resource—the INIT looks only at the very first field of the resource, which contains the major release number, e.g. 6 for System 6.0.5 and the rest.)
Once you’ve got two distinct but recent System and Finder files, one of these sets should be installed as per normal on your hard disk, and the other should be renamed as “System 7” and “Finder 7”, if they are from the System 7 release, or “System 5” and “Finder 5” for Systems previous to release 6.0, regardless of their actual version number. You get the idea. Simple enough, except the Finder doesn’t allow you to rename these files. You can get around this by using a utility like DiskTop or FileMaster which doesn’t have this restriction.
Having renamed the second System and Finder as appropriate, you may do a third one also if you have one. Once all done, drag them into the System folder. Since they have different names from the current System and Finder, they won’t replace them. Also, you should make sure that all System and Finder files are unlocked, otherwise the INIT will be unable to switch the locked ones. You are now ready to try it out!
Instructions
To use this INIT, firstly follow the Installation instructions above. Once this is done, you can use the INIT. If you wish to switch to System 6 (and you aren’t using it already) simply restart the Mac and hold down the ‘6’ key on the keyboard (not the numeric keypad, though) while the startup screen and INIT icons are shown. Unless you have changed the name of the INIT (which comes with a couple of spaces before its name so it will load first) it should be the first or almost first INIT to load. This is good, as it saves you having to go through the INIT sequence twice.
When my INIT operates, it looks to see which key you are holding down, out of ‘5’, ‘6’, ‘7’. If one of these keys are being held down, it then checks if a file called “System ” followed by that number and a file called “Finder ” followed by that number is present in the System folder. If not, then either it is currently in use or not there at all, and does nothing more. If it is there, an icon indicating which System you are switching to is displayed instead of the same one as in the Finder, and the files are renamed so that the requested System and Finder are activated, and the current one is deactivated, along with careful checking so nothing goes wrong. If all is well, a nice zoom effect is drawn and the machine is restarted so the new System and Finder is used.
One problem you may encounter is that some INITs and cdevs may not be compatible with differing versions of the System software, and MultiFinder may not work also. I found that the MultiFinder for System 6.0.5 would not work with System 4.2 (called System 5 by 5-6-7). The simple answer to this problem is to hold down the Command key while starting to avoid MultiFinder when it doesn’t work, and to turn any incompatible INITs etc off temporally (using INIT/cdev or a similar utility) while using the older System.
Future Enhancements
As stated above, this INIT is no longer supported. As such, there will (almost certainly) not be any future versions of it.
I am releasing this INIT as Freeware, which means that you may give it to anyone you like, and you don’t have to send me any money (though I wouldn’t be offended if you did!) Also, you may not charge anything for it, apart for the usual Freeware distribution charges. However, I ask that you send me a letter, postcard or e-mail to register as a user of this program (even if you don’t use it much!) as I maintain a database of my registered users, even for Freeware such as this. If you didn’t get this program from the Dejal Userware disk directly, please make sure you let me know where you got it from. Also, you may be interested in other programs written by me, including some high quality Shareware applications. Write to the address below, or contact me via e-mail, for more information. If you want to receive the Dejal Userware disk, send US$5 or provide your credit card details (I can accept VISA, MasterCard, Bankcard and American Express, as well as cash & checks in any major currency or international money orders) — I can even accept credit card orders via e-mail!
Remember, this program is Freeware, not Shareware, so it is nowhere as good as my Shareware products, and hasn’t had anywhere near as much testing as them. Don’t judge the quality of my paying Shareware efforts based on free hacks like this one. Of course, I can accept no responsibility for any loss in profits, damage or whatever occurring from the use of this program (though let me know if anything like that happens!)
