Contents of the extra/ directory
================================

Data and configuration files to support generation of sos on non-x86
and/or grub-less hosts:
 - dot.mkvars: file to copy as .mkvars in the root directory to
   compile on a non-x86 host, and to generate the grub floppy image on
   a grub-less host
 - grub.img.gz: compressed image of a Grub floppy (without any
   kernel). Used by dot.mkvars.
 - mtoolsrc: file needed by .mkvars to compile a the floppy image

Support of a sos-specific boot sector:
 - Makefile: rules to compile sos_bsect.img, the floppy image with the
   boot sector and the Sos
 - bootsect.S: x86 Sos boot sector (GNU as). Depends on sos_bsect.lds
 - sos_bsect.lds: ld script to bind the boot sector with the remaining
   of the kernel

Misc:
 - qemu-port-e9.diff: patch over qemu to support the bochs "port 0xe9 hack"


What you can do with these files
================================


*** Compile SOS from another architecture:
------------------------------------------
 - compile a cross-compiler for the i586-gnu target. This involves
   compiling the binutils and gcc. Here are example configuration
   options for them:
   binutils (replace sparc-cun-solaris with your arch):
     ../binutils-2.13/configure --prefix=/udd/ddecotig/temp_dd/xgcc/host-sparc-solaris7/stow/binutils-2.11 --host=sparc-sun-solaris2.7 i586-gnu
     make && make install
   gcc (ditto):
     CFLAGS="-O2 -Dinhibit_libc" ../gcc-3.2/configure --target=i586-gnu --prefix=/udd/ddecotig/temp_dd/xgcc/host-sparc-solaris7/stow/gcc-3.2 --with-as=/udd/ddecotig/temp_dd/xgcc/host-sparc-solaris7/bin/as --with-ld=/udd/ddecotig/temp_dd/xgcc/host-sparc-solaris7/bin/ld --with-gnu-as --with-gnu-ld --enable-languages=c --disable-shared --disable-multilib --disable-nls --enable-threads=single
     make && make install
 - compile the mtools
 - copy dot.mkvars to the root directory of SOS, as ".mkvars"
 - customize the CC/LD/... variables to suit your cross-compiler
   installatioon
 - now you may run make from the SOS root directory, it should
   generate the Grub boot floppy image. The following warning is
   normal:
     .mkvars:16: attention : écrasement des commandes pour la cible « grub-sos.img »
     Makefile:92: attention : anciennes commandes ignorées pour la cible « grub-sos.img »


*** To compile SOS from an x86 where grub is not or incorrectly installed:
--------------------------------------------------------------------------
 - copy dot.mkvars to the root directory of SOS, as ".mkvars"
 - customize the CC/LD/... variables to suit your cross-compiler
   installatioon
 - now you may run make from the SOS root directory, it should
   generate the Grub boot floppy image. The following warning is
   normal:
     .mkvars:16: attention : écrasement des commandes pour la cible « grub-sos.img »
     Makefile:92: attention : anciennes commandes ignorées pour la cible « grub-sos.img »


*** To compile SOS with its own bootloader:
-------------------------------------------
 - for cross-architecture compilation: see above
 - cd to this extra/ directory
 - run 'make'
 - the floppy image is: sos_bsect.img
 NOTE : SOS will not boot correctly this way after article 2 !


--
David Decotigny