About loader(8) forth

[Oliver Fromme]

Matteo Riondato <matteo at freebsd.org> wrote:
 >         I'm trying to understand how the loader forth works to see if it's
 > possible to develop something similar to knoppix boot menu and use it
 > for FreeSBIE. 
 > Just to have a try, I replaced /boot/beastie.4th with file a
 > containing only: 
 > 
 > ." Welcome to FreeSBIE"
 > exit
 > 
 > then I deleted the line mentioning beastie-start from /boot/loader.rc
 > and rebooted my machine.
 > 
 > I wanted the machine to print "Welcome to FreeSBIE" and then escape to
 > loader prompt.
 > 
 > Saying it didn't work is probably not enough. I got an error message
 > saying "Compile failed" followed by some codes I didn't had the time
 > to copy because my machine auto-rebooted.

I've modified FreeBSD's standard beastie.4th in the past to
implement various things, although I'm not that much of a
FICL expert either ...   But since nobody else replied, I
give it a try.

I think putting "exit" directly into beastie.4th (which is
included by loader.rc) is not a good idea.  You should use
"exit" only within a function that you define in beastie.4th
and then call that function from loader.rc, just like the
standard files do.

By the way:  When experimenting with the boot loader and
FICL, it is a good idea to run the whole thing under qemu.
It boots a lot faster than a physical machine, even without
qemu-kmod it only takes two or three seconds.  You can
easily mount the image, modify the /boot/* stuff, umount,
start qemu on it, test, stop qemu, mount the image again
and fix things -- all within a few seconds.

If you're looking for documentation, please have a look at
http://ficl.sf.net/ which also has links to several FORTH
primers and tutorials.  Indeed the first of the links points
to a tutorial by J.V.Noble which is easy to read and quite
good.

Best regards
   Oliver

-- 
Oliver Fromme,  secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing
Dienstleistungen mit Schwerpunkt FreeBSD: http://www.secnetix.de/bsd
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