On Sun, 17 Dec 1995, The Great Mr. Kurtz <davagatw@mars.utm.edu> wrote:

> Well, in digging, there *ARE* no code resources in the System folder.  

System FOLDER? or FILE?  I do believe that the Finder has some, but I'm 
not sure.  Probably exists not as "CODE" but as "fcod" or something 
strange, that's one reason the Finder is treated differently than 
applications.  I"ll check on this, if people want me to.

> There are several code-like resources, though.  I finally found one that 
> executes first, but upon putting my own cheap little program in place, 
> the system crashes with a sad mac 0000000F 00000066.

Welcome to the wonderful world of BOOT BLOCKS!  99% of the boot-block 
code I patch crashes with a sad mac.  I'll look tonight to find out what 
the code means.  But I think you took out too much code, and it couldn't 
find a file or something...

> likely that my program's runtime module crashed.  Dunno.  If somebody has 
> a simple program to do something like scramble the video memory or 
> something else that doesn't use any MacOS code, could you drop me a 
> note.

Actually, I already have modified some boot block stuff, and the code 
I've written uses MacOS code, which is FINE, since it's all in the ROM's 
anyway.  I'm in the middle of changing the "happy mac" to a mac which 
sticks its tongue out at you and plays a raspberry sound on the speaker, 
then continues with normal boot.  It's almost finished!

>  I'd like to test this theory, but I don't have any kind of a 
> compiler to build a simple program.  Hmmm.

Well, I"ll tell you my compiler so you can have a good laugh:  I own the 
Motorola Programmer's Reference, which contains the machine opcodes for 
all the assembly commands.  I type out the assembly in ClarisWorks, then 
I hand-compile it by looking in the book!  Yes, that's right folks!   
Hand compiled!  I just ordered C++ from Symantec which has a built-in 
assembler, so maybe I can stop this insanity before it gets too late!  
Aaargh!  I even memorized many of the opcodes!

>  Maybe just resource 0 should 
> be in the strange format and the others should remain as CODE resources.  

CODE resource 0 contains segment-relative procesure offsets, so 
different segments of code can call each other.  There is no real code in 
that resource.

--Rick C. Petty,  aka Snoopy
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