[OpenBIOS] Even more findings to report about booting Mac OS 9

Programmingkid programmingkidx at gmail.com
Sun Apr 17 01:17:52 CEST 2016

I made a program that tells what control characters are in the Mac OS ROM file. It reported that every single control character is in that file. Then I had it only look at the bootscript part. The carriage return and line feed characters are the only control characters found there. 

This page will tell you what the control characters are in case you don't know. 

I added some code to the bootinfo_init_program() function in bootinfo_load.c file that changes all control characters to '\n'. This made Mac OS 9 boot. But when I changed the control characters to a single space, Mac OS 9 failed to boot. This seems strange to me. The space character is the ultimate whitespace character, so why would it fail when '\n' succeeds? My only guess right now is a bug with one of the words in Forth.

Here is the code I used. It is found around line 190 in the file:

while (current < size) {

	c = base[current++];

        // remove all control characters
        if (c >= 0 && c <= 31) {
            c = '\n';

	if (c == '<') {
	    script = 0;
	    tag = 1;
	    taglen = 0;

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