[comp.sys.mac.system] Hacking the Mac intro - New info for any length message.

biswa@janus.Berkeley.EDU (Biswa Ghosh) (12/19/90)

Hi Folks,

Previously I had inquired about hacking the "Welcome to Macintosh" message
to one of my own liking. I had posted a summary, in which I said that it
is possible to change the message to a new one, provided it is no longer
than the old one. Well, *I was wrong*, you can change it to any (reasonable)
length you want. Thanks once again to Lawrence D'Oliveiro, for helping me
figure this one out.

*Warning* - It may be a Bad Thing to hack your system file and you may have
crashes, typhoons, tornadoes, etc. if you do so. If you do make any of the
changes listed below, you do so at your own risk, I assume no responsibility,
blah, blah, blah... These changes should be attempted on a COPY OF your
system file, not on the original. I recommend putting the copy on a floppy,
and booting off the floppy to see if the changes worked, before putting the
modified system file onto your hard disk. Of course, you probably knew all
that.

The welcome message is stored as a DSAT resource, which you can modify with
ResEdit. Unfortunately, it doesn't have a template, so you have to hack it
in hex.

The message is a text item, stored in this format:

							Value
item ID (word)						0032
length of rest of definition (word)			001A
location of text - y coord. (word)			006C
location of text - x coord. (word)			00C0
characters of text (n ASCII bytes, no slashes allowed!) 5765
	This part spells out "Welcome to ..."		6C63
							etc.
null indicating end of text (byte)			0000

So if you want to increase the length of the text (moving along the
following items, and increasing the length of the entire resource),
then you can insert your new text, but also you must update the length
of definition part. So if you increase the message by 4 characters, then
the length, 001A should be replaced with 001E.

I increased the message by an even number of characters only, so that the
word boundaries don't get messed up. Maybe it doesn't matter, but I don't
know.

I also changed the x-location of the message so that it is now nice and
centered above the Macsbug Installed message, whereas before it was
left justified.

All this was done on an SE/30 running system 6.0.4. Your mileage may vary.

Biswa Ghosh
550 Cory Hall				arpa: biswa@janus.berkeley.edu
U.C. Berkeley				uucp: ...ucbvax!janus!biswa
Berkeley, CA 94720			tel:  (415) 642-0395