[net.micro] Half-Gigabit, how to live with ROM

knudsen@ihnss.UUCP (05/10/84)

There is a way to live with software supplied in read-only format
(as on a CD disk) -- it's called a patch file.  Assume your mahine can
load the stuff without jumping to and running it right away.
You can POKE all sorts of fixes into it in RAM before running it.
Next step beyond this is to automate your set of patches, using a simple
interpreter that zaps RAM according to a data file you have built up.
Next step is that software distributors start dealing in such files to
patch the code.
	This is a time-honored scheme in telephone switching systems
code development, wqhere programs in excess of 1 Mbyte take to long
to re-link every time some little bug is found.  More recentlky,
some of us Color Computer owners improve our ROM Basic by copying the
ROMs into RAM, then poking the fixes.
	Some problems with patch files:
1) It's a little more work for everyone
2) programs get bigger and less efficient as more jump-outs are added
3) copy protection may be lost (by letting you load without executing)
4) Given (3), why not just copy CD programs needing patches onto floppies
or winnies and make the patches once?

But, the economies of all that SW and data on one disk may make patch files
well worth the effort.  mike k