Please read the whole text before running the patch program!
What it is for:
This patch eliminates the possibility of switching off a Quadra 840 AV with the Power Key. With the system software delievered with the Macintosh Quadra 840 AV (and probably also the Quadra 660 AV), pressing the Power key (the key to switch on your Mac) will bring up an Alert Box, where you are asked if you "really want to shut down your Macintosh". The Power key is therefore used both for switching on and off your Macintosh (which makes sense, I suppose).
Why it was done:
I wanted to be able to use the control panel PwrSwitcher (by David B. Lamkins) on a Quadra 840 AV. It provides a fast mechanism to switch between programs. You simply press the Power key to switch to the next open (non-hidden) application; there are more options, have a look at the control panel yourself. [Of course, you could simply use the "Require Control key to activate function" option in PwrSwitcher; it makes it possible to use Control-Power key for switching between applications, which will not invoke the Shut down process...]
This also eliminates another potential nuisance: If you constantly end up with the Shut down Alert Box when the only thing you wanted was to drop into the debugger, this patch can help you.
How is it done:
The code to shut down and show the Alert Box is found in the System Enabler 088, which is part of the system software 7.1 for the Macintosh Quadra AV computers. The patch eliminates the call to draw the Alert Box that asks you if you really want to switch off. Instead, it just returns the value corresponding to clicking Cancel in that Alert Box. This all happens in resource lpch, ID=48, starting at offset $4B4.
NOTE: The patch was done on version 1.2 of the System Enabler 088. Although the changes would be identical for older versions, I used version 1.2 to create the patch program, and I only tested the patch program on version 1.2; therefore try to find version 1.2 before you start playing with it (or do it at your own risk). The version of the Enabler can be found in the info box (in the Finder, select the file, and select "Get Info" in the File menu).
Patcher program:
The patcher was produced with ResCompare (version 2.5.3), a very useful program by Michael Hecht. Switch off any virus check program before use (for example by pressing the shift key during start-up). Make a copy of your old System Enabler, and put it in any directory other than your System Folder. Run the patch program: Select the copy you just made in the file list that appears. Click o.k., the patch is then applied (it does its task within a fraction of a second, so don't worry if you can't read the text in the progress dialog...). Remove the old version of the System Enabler (store it in a safe place not directly in the System Folder), copy the patched version into the System Folder, and restart your Quadra.
AND REMEMBER: Only use a copy of the original System Enabler! The patch is done in place, i.e. the changes are applied directly to the copy you select in the patcher program. If you have earlier versions of the System Enabler 088: version 1.2 of the System Enabler 088 is available at ftp.apple.com, and can also be found in the System Update 3.0, I believe.
Compatibility issues:
The only Quadra AV around here is mine, therefore it was the only machine the patched System Enabler was tested with. It doesn't seem to cause problems on that machine, but with another set of inits/cdevs you might run into unexpected conflicts. My machine runs System 7.1, International version.
Problems:
Switching from the Finder to any other application seems to be difficult because the Finder often "swallows" the events caused by pressing the Power key. Press it repeatedly, and the Finder will respond at one point (the number of times varies greatly). I haven't found a way around this problem yet, but I fear the reason is deeply hidden in other code segments of the System Enabler (or the Finder).
What it costs:
Nothing. This is Freeware. Copyright reserved (MF 1995).
Disclaimer:
The author, Markus Frischknecht, is not responsible for any problems or damages caused by the patch program or the patched version of the System Enabler. Use at your own risk.
