DiskDoubler 3.7 is now shipping to registered users. This version provides System 7 compatibility (including balloon help) and a few additional new features that should increase its popularity. Lloyd Chambers of Salient, DiskDoubler's main programmer, increased DiskDoubler's speed significantly in what Salient calls Method A and provided tighter compression in Method B (it was actually Method C for a while, but the old Method B disappeared, so Lloyd renamed it). DiskDoubler now has the best compression ratios available. Other useful features include the ability to create a self-extracting archive that includes as little expansion code as possible, the ability to copy files faster than the Finder using DiskDoubler's normal interface, and, finally, the ability to work in the background. I helped test DiskDoubler, and believe me, it is solid. I use it constantly and have encountered no problems, which is a lot more than I can say for some of the software I test. Alysis, makers of DiskDoubler's competitor SuperDisk!, have yet to send Ken Hancock a copy for testing, but once they do, we will release another TidBITS special issue comparing DiskDoubler and SuperDisk!. My quick tests indicate that DiskDoubler can compress files much more tightly than SuperDisk!, but SuperDisk! is significantly faster. One thing to watch out for is that SuperDisk! does not appear to be verifying what it does, and if the SuperDisk! extension isn't loaded, the compressed files are inaccessible.
System 7 isn't terribly snappy on a slower Mac even if it has plenty of memory, but here's a little trick to use to make it seem slightly faster. Whenever you open or close a window or a launch a file, the Mac shows you the icon opening or closing, providing what are called Zoomrects to simulate motion. Drawing those Zoomrects takes time, so people have come up with a way to eliminate the Zoomrects, which should speed up working in the Finder. Note that we haven't tested these fully yet, but other people have reported no problems with them.
Open a copy of the Finder with ResEdit 2.1
Open the Code resource
Open Code ID 4 (yup, you need to decompress it)
Select Find Offset and look for 0078. This should take you to a line reading 48E7 1F38 594F 2F0F.
Select 4 bytes (i.e., 48E7 1F38)
Replace with the following: 6000 00E6. This represents a BRA instruction around the code that does Zoomrects.
Save the copy of the Finder and close ResEdit.
Put the real Finder in another folder and replace it with your hacked up copy. Reboot. Open a window. Nirvana.
John Heckendorn, who originally posted this, says, "This patch was put together by Danny Brewer at Farallon Computing. I can't guarantee it'll work for you, so proceed with caution. I can say that it certainly works for me. I'll bet it makes Timbuktu Remote operate more quickly, as well :-)."
MacWEEK -- 18-Jun-91, Vol. 5, #23, pg. 5