[Newos-developers] How to boot in Virtual PC

[Jeremy <je...@uc...>]

Hello, mailing list,
This message is mainly for people messing around with NewOS, who find 
(like I did) that they can't boot from the provided floppy images in 
Microsoft Virtual PC.  Hopefully it will occur to those people to browse 
the mailing list archives and they'll see this message :-)

Virtual PC (and maybe bochs; I'm using VPC because I got a free copy 
through MSDN Academic Alliance) needs a complete 720K or 1.44MB floppy 
image in order for it to work, so in the makefile under boot/pc/i386 I 
added the following line, directly after "cat $(STAGE1) 
$(FINAL).prepre.gz > $(FINAL).pre":

cp $(FINAL).pre vpcfork.pre

This way, it doesn't interfere with making the standard floppy image and 
cleaning up after it, but it still gives you a copy of the image before 
the boot block is added so that you can do this:

$ make
...compiler output...
$ boot/pc/i386/makeflop.exe -p 1474560 build/i386-pc/boot/bootblock 
vpcfork.pre newos-vpc.ima
size 574146, blocks 1122 (size 574464)
output file padded to 1474560

Now you have a file called newos-vpc.ima which you can mount to the VPC 
floppy drive before it boots.

Tinkering with NewOS is really fun and great for learning about how an 
operating system is constructed (whereas linux is wayyy too complicated 
at this point).  Maybe this isn't its intended purpose, but it's a handy 
fringe benefit.  Thanks, Travis!

-Jeremy