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diff --git a/contrib/grub4dos-0.4.4/README_GRUB4DOS.txt b/contrib/grub4dos-0.4.4/README_GRUB4DOS.txt new file mode 100644 index 0000000..b2063d7 --- /dev/null +++ b/contrib/grub4dos-0.4.4/README_GRUB4DOS.txt @@ -0,0 +1,3864 @@ +Please refer to http://grub4dos.sourceforge.net/wiki/ for DOCs on GRUB4DOS.
+
+Main project page: https://gna.org/projects/grub4dos/
+
+Download site: http://download.gna.org/grub4dos/
+Download site: http://grub4dos.sourceforge.net/
+Download site: http://sarovar.org/projects/grub4dos/
+Download site: http://grub4dos.nufans.net/
+Download site: http://sites.google.com/site/grubdos/
+Download site: ftp://grub4dos.sarovar.org/pub/grub4dos/
+
+Get the latest source code by using anonymous svn in this way:
+
+ svn co svn://svn.gna.org/svn/grub4dos/trunk grub4dos
+
+or in this way:
+
+ svn co http://svn.gna.org/svn/grub4dos/trunk grub4dos
+
+View the source code online with your web browser at:
+
+ http://svn.gna.org/viewcvs/grub4dos/trunk/
+
+GRUB4DOS mailing list:
+
+ grub4dos-devel@gna.org
+
+Subscription page:
+
+ https://mail.gna.org/listinfo/grub4dos-devel/
+
+Discussion forum(Official technical support site):
+
+ http://www.boot-land.net/forums/index.php?showforum=66
+
+------------------------------------------------------------------------------
+
+Usage:
+ GRUB [--bypass] [--time-out=T] [--hot-key=K] [--config-file=FILE]
+
+ The FILE, for example, can be (hd0,0)/menu.lst
+
+ In CONFIG.SYS, the line looks like:
+
+ install=c:\some\where\grub.exe --config-file=FILE
+
+ If no options present, GRUB.EXE simply uses
+
+ (hd0,0)/menu.lst
+
+ as the configure file, if it exists. (Notice! We finally
+ changed the default file from (hd0,0)/boot/grub/menu.lst to
+ (hd0,0)/menu.lst) (Changed 2006-12-23. See Update 3 below.)
+
+ The partition (hd0,0) can be of a Windows partition or a Linux
+ partition, or any other partition type supported by GRUB.
+
+ Only GRUB-style filename is acceptable here for FILE. A DOS
+ filename won't work(it is certain we should use GRUB-style
+ filenames because DOS-filenames won't access a file in a
+ Linux ext2 partition for example).(See Update 2 below)
+
+ Update: FILE can be the contents of a menu. Use semi-colon
+ to delimitate the embedded commands here in FILE. The FILE
+ can be enclosed with a pair of double-quotes. For example:
+
+ GRUB --config-file="root (hd0,0);chainloader +1"
+
+ This command will boot the system in (hd0,0).
+
+ Another example:
+
+ GRUB --config-file="reboot"
+
+ This command will reboot the machine.
+
+ One more example:
+
+ GRUB --config-file="halt"
+
+ This command will halt the machine.
+
+ if --bypass is specified, GRUB will exit to DOS when
+ timeout reached.
+
+ The option `--time-out=T' specifies the timeout value in
+ seconds. T defaults to 5 if --bypass is specified and defaults
+ to 0 if --bypass is not specified.
+
+ The default hot key value is 0x3920(for space bar). If this
+ key is pressed, GRUB will boot normally. If another key is
+ pressed, GRUB will terminate immediately and return back to
+ DOS. See "int 16 keyboard scan codes" below.
+
+ Each option can be specified only once at most.
+
+ Update 2: DOS filenames have been supported(patched by John
+ Cobb). If the beginning two characters of FILE are "#@", then
+ the rest of FILE is taken as a DOS filename. Example:
+
+ GRUB --config-file="#@c:\menu.lst"
+
+ Only the beginning 4KB of the DOS file will be used. The file
+ should be an uncompressed text file.
+
+ Note: You may also use the `direct DOS file access' with the
+ SHELL or INSTALL line in CONFIG.SYS, but should not use it
+ with the DEVICE line. The DOS document said that a DOS device
+ driver should not call the `open file' DOS call.
+
+ Update 3(2006-12-23): By default, GRUB.EXE will locate its
+ config file in the following order:
+
+ (DOS file) .\menu.lst, the MENU.LST in the current dir.
+
+ (DOS file) \menu.lst, the MENU.LST in the root dir of
+ the current drive.
+ (GRUB file) /menu.lst, the MENU.LST in the root dir of
+ the boot device.
+
+ The default boot device is still (hd0,0).
+
+
+--------------------------------------------------------
+
+Update 1: Version 0.2.0 also brings out a new thing, GRUB for NTLDR,
+ which could be used to boot into GRUB from the boot menu
+ of Windows NT/2000/XP. Copy GRLDR to the root directory of
+ drive C: of Windows NT/2000/XP and append to C:\BOOT.INI
+ this line:
+
+ C:\GRLDR="Start GRUB"
+
+ That will be done. The GRLDR should be in the same directory
+ as BOOT.INI and NTLDR. Note that BOOT.INI is usually hidden
+ and you must unhide it before you can see it. The filename
+ GRLDR shouldn't be changed. If GRLDR is in a NTFS partition,
+ it should be copied to the root directory of another non-NTFS
+ partition(and likewise should the menu.lst file be). If GRLDR
+ is compressed, e.g., in a NTFS partition, it will not work.
+
+ Even if the drive letter of this disk has been changed to
+ other than C by the Windows device manager, it seems you still
+ have to use the letter C here in BOOT.INI, otherwise, NTLDR
+ will fail to locate the GRLDR file.
+
+ And what's more, if you are booting NTLDR from a floppy, you
+ will have to write the GRLDR line in A:\BOOT.INI like this:
+
+ C:\GRLDR="Start GRUB"
+
+ and shouldn't use the letter A like this:
+
+ A:\GRLDR="Start GRUB"
+
+ (Note that in the case when BOOT.INI is on floppy A, the
+ notation "C:\GRLDR" actually refer to the file A:\GRLDR).
+
+
+Update 2: GRUB for Linux is also introduced along with 0.2.0. You can
+ boot grub using a linux loader KEXEC, LILO, SYSLINUX or another
+ GRUB. (GRUB4LIN has merged into GRUB.EXE)
+
+ To boot GRUB off Linux, use this pair of commands:
+
+ kexec -l grub.exe
+ kexec -e
+
+ To boot GRUB via GRUB, use commands like the following:
+
+ kernel (hd0,0)/grub.exe
+ boot
+
+ To boot GRUB via LILO, use these lines in lilo.conf:
+
+ image=/boot/grub.exe
+ label=grub.exe
+
+ To boot GRUB via SYSLINUX, use these lines in syslinux.cfg:
+
+ label grub.exe
+ kernel grub.exe
+
+ LOADLIN may encounter problems when loading grub.exe, because
+ grub.exe requires some unchanged original BIOS interrupt
+ vectors, but DOS has destroyed them, and loadlin does not
+ recover them before it transfers control to grub.exe.
+
+Update 3: Beginning at version 0.4.0, GRUB for DOS supports memdrives.
+ Example:
+
+ # boot into a floppy image
+ map --mem (hd0,0)/floppy.img (fd0)
+ map --hook
+ chainloader (fd0)+1
+ rootnoverify (fd0)
+ map --floppies=1
+ boot
+
+ Because the image will be copied to a memory area, the image
+ itself can be non-contiguous and even gzipped.
+
+ Another Example:
+
+ map --mem=-2880 (hd0,0)/floppy.img (fd0)
+
+ This memdrive (fd0) will occupy at least 1440 KB of memory.
+ This is useful when the size of a 1.44M-floppy image is less
+ than 1440 KB.
+
+ One more example:
+
+ map --mem --read-only (hd0,0)/hd.img (hd1)
+
+ This memdrive is a hard drive, and read-only. That means you
+ will not be able to write data to the memdrive (hd1).
+
+ You can use many memdrives and many ordinary virtual emulated
+ disk-based drives at the same time.
+
+ If the BIOS does not support int15/EAX=e820h, you will not be
+ able to use any memdrives.
+
+Update 4: For memdrive emulation, a single-partition image can be used
+ instead of a whole-harddrive image. Example:
+
+ map --mem (hd0,7)/win98.img (hd0)
+ map --hook
+ chainloader (hd0)+1
+ rootnoverify (hd0)
+ map --harddrives=1
+ boot
+
+ Here win98.img is a partition image without the leading MBR
+ and partition table in it. Surely GRUB for DOS will build an
+ MBR and partition table for the memdrive (hd0).
+
+Update 5: Now GRLDR can be used as a no-emulation-mode bootable CD-ROM
+ boot image. Example for Linux users:
+
+ mkdir iso_root
+ cp grldr iso_root
+ mkisofs -R -b grldr -no-emul-boot -boot-load-seg 0x1000 -o bootable.iso iso_root
+
+ As an alternative, grldr can also be used the same way as
+ stage2_eltorito. The -boot-info-table option is allowed but you
+ can omit it:
+
+ mkdir iso_root
+ cp grldr iso_root
+ mkisofs -R -b grldr -no-emul-boot -boot-load-size 4 -o grldr.iso iso_root
+
+ Also note that the bootable.iso above must be created with the
+ -boot-load-seg 0xHHHH option where HHHH is greater than or
+ equal to 1000(hex). If HHHH < 1000(hex), QEMU will hang. This
+ is a bug in QEMU. The grldr.iso can be created with or without
+ -boot-load-seg 0xHHHH option.
+
+ The menu.lst file should be placed in the root dir of the CD.
+
+Update 6: The Chinese special build is in the "chinese" subdirectory.
+ (patched by Gandalf, 2005-06-27)
+
+ The Chinese special build also has scdrom builtin.
+ (update: scdrom has been dropped since 2006-07-20)
+
+Update 7: Added memory drive (md). Like (nd) for network drive and (cd)
+ for CD-ROM drive, a new drive (md) is implemented for accessing
+ the whole memory as a disk drive. (md) only works for systems
+ with BIOS int15/EAX=E820h support.
+
+ The cat command now has a few new options: --hex for hexdump,
+ and --locate=STRING for string search in file.
+
+ Typical examples:
+
+ cat --hex (hd0)+1
+
+ It will display the MBR sector in hex form.
+
+ cat --hex (md)+2
+
+ It will display 1KB of your memory(in fact, it is the real-mode
+ IDT table), also in hexdump form.
+
+ cat --hex (md)0x800+1
+
+ It will display 1 sector of your extended memory.
+
+ cat --hex (hd0,0)+1
+
+ It will display the first sector of partition (hd0,0). Usually
+ this sector contains the boot record of an operating system.
+
+Update 8: Added ram drive (rd). The (md) device accesses the memory
+ starting at physical address 0. But (rd) accesses memory
+ starting at any base address. The base and length of the ram
+ drive can be specified through the map command. "help map" for
+ details. You can even specify the BIOS drive number used for
+ the (rd) drive, e.g., map --ram-drive=0xf0. The default drive
+ number for (rd) is 0x7F which is a floppy. If (rd) is a hard
+ drive image, you should change the drive number to a value
+ greater than or equal to 0x80(but should avoid using 0xffff,
+ because 0xffff is for the (md) device).
+
+ The notation (rd)+1 always represents the file which contains
+ all the bytes stored in (rd).
+
+Update 9: Directly boot NTLDR of WinNT/2K/XP and IO.SYS of Win9x/ME and
+ KERNEL.SYS of FreeDOS. Examples:
+
+ chainloader --edx=0xPPYY (hd0,0)/ntldr
+ boot
+
+ chainloader --edx=0xYY (hd0,0)/io.sys
+ boot
+
+ chainloader --ebx=0xYY (hd0,0)/kernel.sys
+ boot
+
+ Hex YY specifies the boot drive number, and hex PP specifies
+ the boot partition number of NTLDR. If the boot drive is
+ floppy, PP should be the hex value ff, i.e., decimal 255.
+
+ For KERNEL.SYS of FreeDOS, the --edx won't work,
+ use --ebx please.
+
+ The option --edx ( --ebx ) can be omitted if the file is in
+ its normal place. But in some cases, those options are needed.
+
+ If, e.g., the ntldr file is in an ext2 partition called
+ (hd2,8) while you want it to think of the Windows partition
+ (hd0,7) as the boot partition, then --edx is required:
+
+ chainloader --edx=0x0780 (hd2,8)/ntldr
+
+ For DOS kernels(i.e., IO.SYS and KERNEL.SYS), the boot
+ partition number is meaningless, so you only need to specify
+ the correct boot drive number YY(but specifying the boot
+ partition number is harmless).
+
+ The above PPYY can also be specified by using a root or
+ rootnoverify command after the chainloader command. Examples:
+
+ chainloader (hd2,6)/kernel.sys
+ rootnoverify (hd0) <-------- YY=80
+ boot
+
+ chainloader (hd0,0)/ntldr
+ rootnoverify (hd0,5) <-------- YY=80, PP=05
+ boot
+
+ Tip: CMLDR (the ComMand LoaDeR, which is used to load the
+ Windows Fault Recovery Console) can be chainloaded as well
+ as NTLDR.
+
+ Bean has successfully decompressed and booted IO.SYS of WinME.
+ Thanks for the great job!
+
+Update 10: isolinux.bin (version 3.73) can be chainloaded as with build
+ 2009-02-09.
+
+ chainloader (cd)/isolinux.bin
+
+ isolinux.bin must reside in a real or virtual cdrom.
+
+Update 11: stage2 of Grub Legacy can be chainloaded in this way:
+
+ chainloader --force --load-segment=0 --load-offset=0x8000 --boot-cs=0 --boot-ip=0x8200 (...)/.../stage2
+
+--------------------------------------------------------
+
+ There is no full documentation in English at present. Here are some
+ examples showing the usage of disk emulation commands:
+
+1. Emulates HD partition C: as floppy drive A: and boot win98 from C:
+
+ map --read-only (hd0,0)+1 (fd0)
+ chainloader (hd0,0)+1
+ rootnoverify (hd0)
+ boot
+
+ In the above example, (hd0,0) is drive C: with win98 on it. After win98
+ boot complete, you will find that A: contains all files of C:, and if
+ you delete files in A:, the files in C: will also disappear.
+
+ At the map command line, the notation (hdm,n)+1 is interpreted to
+ represent the whole partition (hdm,n), not just the first sector of the
+ partition.
+
+2. Emulates HD partition C: as floppy drive A: and boot win98 from A:
+
+ map --read-only (hd0,0)+1 (fd0)
+ map --hook
+ chainloader (fd0)+1
+ rootnoverify (fd0)
+ map --floppies=1
+ boot
+
+ After the "map --hook" command, the emulation takes effect instantly
+ even in the GRUB command line.
+
+ Note that the (fd0) in "chainloader (fd0)+1" is the emulated virtual
+ floppy A:, not the real floppy diskette(because map is hooked now).
+
+
+3. Emulates an image file as floppy drive A: and boot win98 from C:
+
+ map --read-only (hd0,0)/floppy.img (fd0)
+ chainloader (hd0,0)+1
+ rootnoverify (hd0)
+ map --floppies=1
+ map --harddrives=1
+ boot
+
+4. Emulates an HD partition as the first hard disk and boot DOS from it:
+
+ map --read-only (hd2,6)+1 (hd0)
+ map --hook
+ chainloader (hd0,0)+1
+ rootnoverify (hd0)
+ map --harddrives=1
+ boot
+
+ In this example, (hd2,6)+1 represents an extended logical DOS partition
+ of the third BIOS hard disk (hd2).
+
+ If a DOS partition is used to emulate a hard disk, GRUB for DOS will
+ first try to locate the partition table, usually 63 sectors ahead of
+ the DOS partition. GRUB for DOS will refuse the emulation if the
+ partition table is not there.
+
+5. Emulates an image file as the first hard disk and boot DOS from it:
+
+ map --read-only (hd0,0)/harddisk.img (hd0)
+ chainloader --load-length=512 (hd0,0)/harddisk.img
+ rootnoverify (hd0)
+ map --harddrives=1
+ boot
+
+ If an image file is used to emulate a hard disk, the image file must
+ contain an MBR. In other word, the first sector of HARDDISK.IMG must
+ contain the partition table of the emulated virtual hard disk.
+
+Note: Counters for floppies and harddrives in the BIOS Data Area remain
+ unchanged during the mapping. You should manually set them to proper
+ values with `map --floppies=' and/or `map --harddrives=', especially,
+ e.g., when there is no real floppy drive attached to the mother board.
+ If not doing so, DOS might fail to start.
+
+ `map --status' can report the values. Note also that `map --floppies='
+ and `map --harddrives=' can be used independently without the
+ appearance of mappings.
+
+ 0.4.2 has introduced a new variable, memdisk_raw, to simulate the
+ memdisk-like raw mode. If the BIOS has no int15/87h, or if it has
+ buggy int15/87h support, you should set this variable before any
+ memdrives are used. Here is an example:
+
+ map --memdisk-raw=1
+ map --mem (hd0,0)/floppy.img (fd0)
+ map --hook
+ chainloader (fd0)+1
+ rootnoverify (fd0)
+ boot
+
+ If you encountered a memdrive failure without using
+ map --memdisk-raw=1, you should have a try with `map --memdisk-raw=1'.
+
+ If you `map --memdisk-raw=0' later, you should afterwards do a
+ `map --unhook'(and followed by a `map --hook' if needed).
+
+ Update: memdisk_raw now defaults to 1. You should `map --memdisk-raw=0'
+ if you want to use int15/87h to access memdrives.
+
+--------------------------------------------------------
+
+ Floppies/harddisks of any size can be emulated with GRUB for DOS 0.2.0.
+
+ Image file must be contiguous, or else GRUB for DOS will refuse it.
+
+ The `blocklist' command can list fragments or pieces of a file.
+
+ Type "help map" at the GRUB prompt to get a brief description of the
+ command.
+
+ The form
+
+ map ... (fd?)
+
+ is a floppy emulation, and the form
+
+ map ... (hd?)
+
+ is a hard disk emulation.
+
+ When a HARD DISK emulation is used, better not start Windows for
+ security reasons. Windows may even destroy all data and all information
+ on all your real hard disks!!!!!!!!
+
+ Update for --mem: when --mem is used, it seems rather safe even after
+ entering Windows. Win98 can operate the memdrive normally.
+
+ Windows NT/2000/XP does not recognize the emulated drives no matter
+ whether the --mem option is present.
+
+
+
+******************************************************************************
+*** Explanation of the grldr-bootable floppies or harddisk partitions ***
+******************************************************************************
+
+1. Ext2 Boot Sector/Boot Record Layout (for loading grldr)
+------------------------------------------------------------------------------
+An EXT2/EXT3 volume can be GRUB-bootable. Copy grldr and an optional menu.lst
+to the root dir of the EXT2/EXT3 volume, and build the boot sector based on the
+fifth sector of grldr(some fields need to be changed as detailed in the
+following table). And then the EXT2/EXT3 volume is GRUB-bootable.
+
+Update: bootlace.com is a DOS/Linux utility that can install the GRLDR boot
+record onto the first sector of an EXT2/EXT3 volume.
+
+Offset Length Description
+====== ====== ==============================================================
+00h 2 Machine code for short jump over the data.
+
+02h 1 LBA indicator. Valid values are 0x02 for CHS mode, or 0x42 for
+ LBA mode.
+
+ If the BIOS int13 supports LBA, this byte can be safely set to
+ 0x42.
+
+ Some USB BIOSes might have bugs when using CHS mode, so the
+ format program should set this byte to 0x42. It seems that
+ (generally) all USB BIOSes have LBA support.
+
+ If the format program does not know whether the BIOS has LBA
+ support, it may operate this way:
+
+ if (partition_start + total_sectors_in_partition) exceeds the
+ CHS addressing ability(especially when it is greater than
+ 1024*256*63), the caller should set this byte to 0x42,
+ otherwise, set to 0x02.
+
+ Note that Windows98 uses the value 0x0e as the LBA indicator.
+
+ Update: this byte of LBA indicator is ignored. The boot
+ record can probe the LBA support of BIOS.
+
+03h 10 OEM name string (of OS which formatted the disk).
+ Update: this field is now used for error message of "I/O error"
+
+0Dh 1 Sectors per block. Valid values are 2, 4, 8, 16 and 32.
+
+0Eh 2 Bytes per block. Valid values are 0x400, 0x800, 0x1000, 0x2000
+ and 0x4000.
+
+10h 4 Pointers in pointers-per-block blocks, that is, number of
+ blocks covered by a double-indirect block.
+
+ Valid values are 0x10000, 0x40000, 0x100000, 0x400000 and
+ 0x1000000.
+
+14h 4 Pointers per block, that is, number of blocks covered by an
+ indirect block.
+
+ Valid values are 0x100, 0x200, 0x400, 0x800, 0x1000.
+
+18h 2 Sectors per track.
+
+1Ah 2 Number of heads/sides.
+
+1Ch 4 Number of hidden sectors (those preceding the boot sector).
+
+ Also referred to as the starting sector of the partition.
+
+ For floppies, it should be 0.
+
+20h 4 Total number of sectors in the filesystem(or in the partition).
+
+24h 1 BIOS drive number of the boot device.
+
+ Actually this byte is ignored for read. The boot code will
+ write DL onto this byte. The BIOS or the caller should set
+ drive number in DL.
+
+ We assume all BIOSes pass correct drive number in DL.
+ Buggy BIOSes are not supported!!
+
+25h 1 Partition number of this partition on the boot drive.
+
+ 0, 1, 2, 3 are primary partitions.
+ 4, 5, 6, ... are logical partitions in the extended partition.
+
+ 0xff is for whole drive. So for floppies, it should be 0xff.
+
+26h 2 inode size in bytes. (Notice! We use the formerly reserved
+ word here for inode size!)
+
+28h 4 Number of inodes per group.
+
+ Normally a 1.44M floppy has only one group, and the total
+ number of inodes is 184. So the value should be 184 or
+ greater.
+
+2Ch 4 The block number for group descriptors.
+
+ Valid values are 2 for 1024-byte blocks, and 1 otherwise.
+
+ The value here is equal to (s_first_data_block + 1).
+
+30h 1 code for "cld"(0xFC).
+
+31h 2 code for "xor ax,ax"(0x31, 0xC0).
+
+33h 1 code for "nop"(0x90) or "cwd"(0x99)
+
+34h 458 The rest of the machine code.
+
+1FEh 2 Boot Signature AA55h.
+
+
+2. FAT12/FAT16 Boot Sector/Boot Record Layout (for loading grldr)
+------------------------------------------------------------------------------
+A FAT12/16 volume can be GRUB-bootable. Copy grldr and an optional menu.lst to
+the root dir of the FAT12/16 volume, and build the boot sector based on the
+fourth sector of grldr(some fields need to be changed as detailed in the
+following table). And then the FAT12/16 volume is GRUB-bootable.
+
+Update: bootlace.com is a DOS/Linux utility that can install the GRLDR boot
+record onto the boot sector of an FAT12/16 volume.
+
+Offset Length Description
+====== ====== ==============================================================
+00h 2 Machine code for short jump over the data.
+
+02h 1 LBA indicator. Valid values are 0x90 for CHS mode, or 0x0e for
+ LBA mode.
+
+ If the BIOS int13 supports LBA, this byte can be safely set to
+ 0x0e.
+
+ Some USB BIOSes might have bugs when using CHS mode, so the
+ format program should set this byte to 0x0e. It seems that
+ (generally) all USB BIOSes have LBA support.
+
+ If the format program does not know whether the BIOS has LBA
+ support, it may operate this way:
+
+ if (partition_start + total_sectors_in_partition) exceeds the
+ CHS addressing ability(especially when it is greater than
+ 1024*256*63), the caller should set this byte to 0x0e,
+ otherwise, set to 0x90.
+
+ Update: this byte of LBA indicator is ignored. The boot
+ record can probe the LBA support of BIOS.
+
+ Update(2006-07-31): Though GRLDR won't use this LBA-indicator
+ byte, Windows 98 uses it. Usually this byte should be 0x90 for
+ CHS mode(especially for floppies). If this byte is not set
+ properly, Windows 98 will not recognize the floppy or
+ partition. This problem was reported by neiljoy. Many thanks!
+
+03h 8 OEM name string (of OS which formatted the disk).
+
+0Bh 2 Bytes per sector. Must be 512.
+
+0Dh 1 Sectors per cluster. Valid values are 1, 2, 4, 8, 16, 32, 64
+ and 128. But a cluster size larger than 32K should not occur.
+
+0Eh 2 Reserved sectors(number of sectors before the first FAT,
+ including the boot sector), usually 1.
+
+10h 1 Number of FATs(nearly always 2).
+
+11h 2 Maximum number of root directory entries.
+
+13h 2 Total number of sectors (for small disks only, if the disk is
+ too big this is set to 0 and offset 20h is used instead).
+
+15h 1 Media descriptor byte, pretty meaningless now (see below).
+
+16h 2 Sectors per FAT.
+
+18h 2 Sectors per track.
+
+1Ah 2 Total number of heads/sides.
+
+1Ch 4 Number of hidden sectors (those preceding the boot sector).
+
+ Also referred to as the starting sector of the partition.
+
+ For floppies, it should be 0.
+
+20h 4 Total number of sectors for large disks.
+
+24h 1 BIOS drive number of the boot device.
+
+ Actually this byte is ignored for read. The boot code will
+ write DL onto this byte. The BIOS or the caller should set
+ drive number in DL.
+
+ We assume all BIOSes pass correct drive number in DL.
+ Buggy BIOSes are not supported!!
+
+25h 1 Partition number of this filesystem in the boot drive.
+
+ This byte is ignored for read. The boot code will write
+ partition number onto this byte. See offset 41h below.
+
+26h 1 Signature (must be 28h or 29h to be recognised by NT).
+
+27h 4 Volume serial number.
+
+2Bh 11 Volume label.
+
+36h 8 File system ID. "FAT12 ", "FAT16 " or "FAT ".
+
+3Eh 1 code for "cli".
+
+3Fh 1 code for "cld".
+
+40h 1 code for "mov dh, imm8".
+
+41h 1 Partition number of this partition on the boot drive.
+
+ 0, 1, 2, 3 are primary partitions.
+ 4, 5, 6, ... are logical partitions in the extended partition.
+
+ 0xff is for whole drive. So for floppies, it should be 0xff.
+
+42h 442 The rest of the machine code.
+
+1FCh 4 Boot Signature AA550000h. (Win9x uses 4 bytes as magic value)
+
+
+3. FAT32 Boot Sector/Boot Record Layout (for loading grldr)
+------------------------------------------------------------------------------
+A FAT32 volume can be GRUB-bootable. Copy grldr and an optional menu.lst to
+the root dir of the FAT32 volume, and build the boot sector based on the
+third sector of grldr(some fields need to be changed as detailed in the
+following table). And then the FAT32 volume is GRUB-bootable.
+
+Update: bootlace.com is a DOS/Linux utility that can install the GRLDR boot
+record onto the boot sector of an FAT32 volume.
+
+Offset Length Description
+====== ====== ==============================================================
+00h 2 Machine code for short jump over the data.
+
+02h 1 LBA indicator. Valid values are 0x90 for CHS mode, or 0x0e for
+ LBA mode.
+
+ If the BIOS int13 supports LBA, this byte can be safely set to
+ 0x0e.
+
+ Some USB BIOSes might have bugs when using CHS mode, so the
+ format program should set this byte to 0x0e. It seems that
+ (generally) all USB BIOSes have LBA support.
+
+ If the format program does not know whether the BIOS has LBA
+ support, it may operate this way:
+
+ if (partition_start + total_sectors_in_partition) exceeds the
+ CHS addressing ability(especially when it is greater than
+ 1024*256*63), the caller should set this byte to 0x0e,
+ otherwise, set to 0x90.
+
+ Update: this byte of LBA indicator is ignored. The boot
+ record can probe the LBA support of BIOS.
+
+ Update(2006-07-31): Though GRLDR won't use this LBA-indicator
+ byte, Windows 98 uses it. Usually this byte should be 0x90 for
+ CHS mode(especially for floppies). If this byte is not set
+ properly, Windows 98 will not recognize the floppy or
+ partition. This problem was reported by neiljoy. Many thanks!
+
+03h 8 OEM name string (of OS which formatted the disk).
+
+0Bh 2 Bytes per sector. Must be 512.
+
+0Dh 1 Sectors per cluster. Valid values are 1, 2, 4, 8, 16, 32, 64
+ and 128. But a cluster size larger than 32K should not occur.
+
+0Eh 2 Reserved sectors(number of sectors before the first FAT,
+ including the boot sector), usually 1.
+
+10h 1 Number of FATs(nearly always 2).
+
+11h 2 (Maximum number of root directory entries)Must be 0.
+
+13h 2 (Total number of sectors for small disks only)Must be 0.
+
+15h 1 Media descriptor byte, pretty meaningless now (see below).
+
+16h 2 (Sectors per FAT)Must be 0.
+
+18h 2 Sectors per track.
+
+1Ah 2 Total number of heads/sides.
+
+1Ch 4 Number of hidden sectors (those preceding the boot sector).
+
+ Also referred to as the starting sector of the partition.
+
+ For floppies, it should be 0.
+
+20h 4 Total number of sectors for large disks.
+
+24h 4 FAT32 sectors per FAT.
+
+28h 2 If bit 7 is clear then all FATs are updated, otherwise bits
+ 0-3 give the current active FAT, all other bits are reserved.
+
+2Ah 2 High byte is major revision number, low byte is minor revision
+ number, currently both are 0.
+
+2Ch 4 Root directory starting cluster.
+
+30h 2 File system information sector.
+
+32h 2 If non-zero this gives the sector which holds a copy of the
+ boot record, usually 6.
+
+34h 12 Reserved, set to 0.
+
+40h 1 BIOS drive number of the boot device.
+
+ 80h is first HDD, 00h is first FDD.
+
+ Actually this byte is ignored for read. The boot code will
+ write DL onto this byte. The BIOS or the caller should set
+ drive number in DL.
+
+ We assume all BIOSes pass correct drive number in DL.
+ Buggy BIOSes are not supported!!
+
+41h 1 Partition number of this filesystem in the boot drive.
+
+ This byte is ignored for read. The boot code will write
+ partition number onto this byte. See offset 5Dh below.
+
+42h 1 Signature (must be 28h or 29h to be recognised by NT).
+
+43h 4 Volume serial number.
+
+47h 11 Volume label.
+
+52h 8 File system ID. "FAT32 ".
+
+5Ah 1 opcode for "cli".
+
+5Bh 1 opcode for "cld".
+
+5Ch 1 opcode for "mov dh, imm8".
+
+5Dh 1 Partition number of this partition on the boot drive.
+
+ 0, 1, 2, 3 are primary partitions.
+ 4, 5, 6, ... are logical partitions in the extended partition.
+
+ 0xff is for whole drive. So for floppies, it should be 0xff.
+
+5Eh 414 The rest of the machine code.
+
+1FCh 4 Boot Signature AA550000h. (Win9x uses 4 bytes as magic value)
+
+
+4. NTFS Boot Sector/Boot Record Layout (for loading grldr)
+------------------------------------------------------------------------------
+An NTFS volume can be GRUB-bootable. Copy grldr and an optional menu.lst to
+the root dir of the NTFS volume, and build the boot sector based on the
+6th-9th sectors of grldr(some fields need to be changed as detailed in the
+following table). And then the NTFS volume is GRUB-bootable.
+
+Update: bootlace.com is a DOS/Linux utility that can install the GRLDR boot
+record onto the leading 4 sectors of an NTFS volume.
+
+Offset Length Description
+====== ====== ==============================================================
+00h 2 Machine code for short jump over the data.
+
+02h 1 LBA indicator. Valid values are 0x90 for CHS mode, or 0x0e for
+ LBA mode.
+
+ If the BIOS int13 supports LBA, this byte can be safely set to
+ 0x0e.
+
+ Some USB BIOSes might have bugs when using CHS mode, so the
+ format program should set this byte to 0x0e. It seems that
+ (generally) all USB BIOSes have LBA support.
+
+ If the format program does not know whether the BIOS has LBA
+ support, it may operate this way:
+
+ if (partition_start + total_sectors_in_partition) exceeds the
+ CHS addressing ability(especially when it is greater than
+ 1024*256*63), the caller should set this byte to 0x0e,
+ otherwise, set to 0x90.
+
+ Update: this byte of LBA indicator is ignored. The boot
+ record can probe the LBA support of BIOS.
+
+ Update(2006-07-31): Though GRLDR won't use this LBA-indicator
+ byte, Windows 98 uses it. Usually this byte should be 0x90 for
+ CHS mode(especially for floppies). If this byte is not set
+ properly, Windows 98 will not recognize the floppy or
+ partition. This problem was reported by neiljoy. Many thanks!
+
+03h 8 OEM name string (of OS which formatted the disk).
+
+0Bh 2 Bytes per sector. Must be 512.
+
+0Dh 1 Sectors per cluster. Valid values are 1, 2, 4, 8, 16, 32, 64
+ and 128. But a cluster size larger than 32K should not occur.
+
+0Eh 2 (Reserved sectors)Unused.
+
+10h 1 (Number of FATs)Must be 0.
+
+11h 2 (Maximum number of root directory entries)Must be 0.
+
+13h 2 (Total number of sectors for small disks only)Must be 0.
+
+15h 1 Media descriptor byte, pretty meaningless now (see below).
+
+16h 2 (Sectors per FAT)Must be 0.
+
+18h 2 Sectors per track.
+
+1Ah 2 Total number of heads/sides.
+
+1Ch 4 Number of hidden sectors (those preceding the boot sector).
+
+ Also referred to as the starting sector of the partition.
+
+ For floppies, it should be 0.
+
+20h 4 (Total number of sectors for large disks)Must be 0.
+
+24h 4 (FAT32 sectors per FAT) - Usually 80 00 80 00, A value of
+ 80 00 00 00 has been seen on a USB thumb drive which is
+ formatted with NTFS under Windows XP. Note this is removable
+ media and is not partitioned, the drive as a whole is NTFS
+ formatted.
+
+28h 8 Number of sectors in the volume.
+
+30h 8 LCN of VCN 0 of the $MFT.
+
+38h 8 LCN of VCN 0 of the $MFTMirr.
+
+40h 4 Clusters per MFT Record.
+
+44h 4 Clusters per Index Record.
+
+48h 8 Volume serial number.
+
+50h 4 Checksum, usually 0.
+
+54h 1 opcode for "cli".
+
+55h 1 opcode for "cld".
+
+56h 1 opcode for "mov dh, imm8".
+
+57h 1 Partition number of this partition on the boot drive.
+
+ 0, 1, 2, 3 are primary partitions.
+ 4, 5, 6, ... are logical partitions in the extended partition.
+
+ 0xff is for whole drive. So for floppies, it should be 0xff.
+
+58h 420 The rest of the machine code in the first sector.
+
+1FCh 4 Boot Signature AA550000h. (Win9x uses 4 bytes as magic value)
+
+200h 1536 The rest of the machine code in the last 3 sectors.
+
+------------------------------------------------------------------------------
+
+Appendix A: File System Information Sector of FAT32(not used by grldr)
+
+Offset Length Description
+====== ====== ==============================================================
+0h 4 Leading Signature 41615252h.
+
+4h 480 Reserved, set to 0.
+
+1E4h 4 FSI structure signature 61417272h.
+
+1E8h 4 Contains the last known count of free clusters, if this is
+ equal to FFFFFFFFh, then the count is unknown.
+
+1ECh 4 Cluster number at which you should begin a search for a free
+ cluster, if this is equal to FFFFFFFFh then the field has not
+ been set.
+
+1F0h 12 Reserved, set to 0.
+
+1FCh 4 Trailing Signature AA550000h.
+
+------------------------------------------------------------------------------
+
+Appendix B: Media Descriptor Byte(not used by grldr)
+
+The Media descriptor byte is meaningless because of the duplications, F0h for
+example.
+
+Byte Type of disk Sectors Heads Tracks Capacity
+---- ------------ ------- ----- ------ --------
+FFh 5 1/4" 8 2 40 320KB
+FEh 5 1/4" 8 1 40 160KB
+FDh 5 1/4" 9 2 40 360KB
+FCh 5 1/4" 9 1 40 180KB
+FBh both 9 2 80 640KB
+FAh both 9 1 80 320KB
+F9h 5 1/4" 15 2 80 1200KB
+F9h 3 1/2" 9 2 80 720KB
+F0h 3 1/2" 18 2 80 1440KB
+F0h 3 1/2" 36 2 80 2880KB
+F8h hard disk NA NA NA NA
+
+******************************************************************************
+*** grldr.mbr - How to write it to Master Boot Track of the hard disk ***
+******************************************************************************
+
+grldr.mbr contains code that can be used as Master Boot Record. The code is
+responsible for searching all partitions for grldr and when found, loading it.
+Currently supported partition types are: FAT12/FAT16/FAT32, NTFS, EXT2/EXT3.
+Logical partitions in the extended partition are supported, provided that the
+extended partition type is Microsoft-compatible. In fact, the Linux extended
+partition type(0x85) is not fully tested for the search mechanism.
+
+How to write GRLDR.MBR to the Master Boot Track of a hard disk?
+
+First, read the Windows disk signature and partition information bytes
+(72 bytes in total, from offset 0x01b8 to 0x01ff of the MBR sector), and put
+them on the same range from offset 0x01b8 to 0x01ff of the beginning sector of
+GRLDR.MBR.
+
+Optionally, if the MBR in the hard disk is a single sector MBR created by
+Microsoft FDISK, it may be copied onto the second sector of GRLDR.MBR.
+
+The second sector of GRLDR.MBR is called "previous MBR". When GRLDR not found,
+"previous MBR" will be started.
+
+No other steps needed, after all necessary changes stated above have been made,
+now simply write GRLDR.MBR on to the Master Boot Track. That's all.
+
+Note: The Master Boot Track means the first track of the hard drive.
+
+Note: The bootstrap code of GRLDR.MBR only finds GRLDR file in the root dir of
+a partition. You'd better place menu.lst file accompanying with GRLDR(i.e., in
+the same root dir of the same partition as GRLDR).
+
+The filename "grldr" in an ext2 partition must be in lower case letters, and
+the file type of grldr must be plain regular. Other types, e.g., a symbolic
+link, won't work.
+
+Update: bootlace.com is a DOS/Linux utility for installing grldr.mbr to MBR.
+The whole grldr.mbr is embedded in the body of the bootlace.com utility, so
+bootlace.com can be used independently. See below.
+
+******************************************************************************
+*** grldr.mbr - Details about the control bytes ***
+******************************************************************************
+
+Six bytes can be used to control the boot process of GRLDR.MBR.
+
+Offset Length Description
+====== ====== ==============================================================
+02h 1 bit0=1: disable the search for GRLDR on floppy
+ bit0=0: enable the search for GRLDR on floppy
+
+ bit1=1: disable the boot of PREVIOUS MBR with invalid
+ partition table(usually an OS boot sector)
+ bit1=0: enable the boot of PREVIOUS MBR with invalid
+ partition table(usually an OS boot sector)
+
+ bit2=1: disable the feature of unconditional entrance to
+ the command-line(See below `--duce')
+ bit2=0: enable the feature of unconditional entrance to
+ the command-line(See below `--duce')
+
+ bit3=1: disable geometry tune(See below `--chs-no-tune')
+ bit3=0: enable geometry tune(See below `--chs-no-tune')
+
+ bit4 - bit6: reserved
+
+ bit7=1: try to boot PREVIOUS MBR after the search for GRLDR
+ bit7=0: try to boot PREVIOUS MBR before the search for GRLDR
+
+03h 1 timeout in seconds to wait for a key press. 0xff stands for
+ waiting all the time(endless).
+
+04h 2 hot-key code. high byte is scan code, low byte is ASCII code.
+ the default value is 0x3920, which stands for the space bar.
+ if this key is pressed, GRUB will be started prior to the boot
+ of previous MBR. See "int 16 keyboard scan codes" below.
+
+06h 1 preferred boot drive number, 0xff for no-drive
+07h 1 preferred partition number, 0xff for whole drive
+
+ if the preferred boot drive number is 0xff, the order of the
+ search for GRLDR will be:
+
+ (hd0,0), (hd0,1), ..., (hd0,L),(L=max partition number)
+ (hd1,0), (hd1,1), ..., (hd1,M),(M=max partition number)
+ ... ... ... ... ... ... ... ...
+ (hdX,0), (hdX,1), ..., (hdX,N),(N=max partition number)
+ (X=max harddrive number)
+ (fd0)
+
+ otherwise, if the preferred boot drive number is Y(not equal to
+ 0xff) and the preferred partition number is K, then the order of
+ the search for GRLDR will be:
+
+ (Y) if K=0xff; or (Y,K) otherwise
+ (hd0,0), (hd0,1), ..., (hd0,L),(L=max partition number)
+ (hd1,0), (hd1,1), ..., (hd1,M),(M=max partition number)
+ ... ... ... ... ... ... ... ...
+ (hdX,0), (hdX,1), ..., (hdX,N),(N=max partition number)
+ (X=max harddrive number)
+ (fd0)
+
+ Note: if Y < 0x80, then (Y) is floppy, else (Y) is harddrive,
+ and (Y,K) is partition number K on harddrive (Y).
+
+
+******************************************************************************
+*** bootlace.com - Install GRLDR.MBR bootstrap code to MBR ***
+******************************************************************************
+
+BOOTLACE.COM installs GRLDR.MBR boot record to the MBR of a harddrive or of a
+harddrive image file, or to the boot sector of a floppy or a floppy image.
+
+Usage:
+
+ bootlace.com [OPTIONS] DEVICE_OR_FILE
+
+OPTIONS:
+
+ --read-only do everything except the actual write to the
+ specified DEVICE_OR_FILE.
+
+ --restore-mbr restore the previous mbr.
+
+ --mbr-no-bpb do not copy BPB in the boot sector of the
+ leading FAT partition to MBR.
+
+ --no-backup-mbr do not copy the old MBR to the second sector of
+ DEVICE_OR_FILE.
+
+ --force-backup-mbr force the copy of old MBR to the second sector
+ of DEVICE_OR_FILE.
+
+ --mbr-enable-floppy enable the search for GRLDR on floppy.
+
+ --mbr-disable-floppy disable the search for GRLDR on floppy.
+
+ --mbr-enable-osbr enable the boot of PREVIOUS MBR with invalid
+ partition table(usually an OS boot sector).
+
+ --mbr-disable-osbr disable the boot of PREVIOUS MBR with invalid
+ partition table(usually an OS boot sector).
+
+ --duce disable the feature of unconditional entrance
+ to the command-line.
+
+ Normally one can unconditionally get the
+ command-line console by a keypress of `C',
+ bypassing all config-files(including the
+ preset-menu). This is a security hole. So we
+ need this option to disable the feature.
+
+ DUCE is for Disable Unconditional Command-line
+ Entrance.
+
+ --chs-no-tune disable the feature of geometry tune.
+
+ --boot-prevmbr-first try to boot PREVIOUS MBR before the search for
+ GRLDR.
+
+ --boot-prevmbr-last try to boot PREVIOUS MBR after the search for
+ GRLDR.
+
+ --preferred-drive=D preferred boot drive number, 0 <= D < 255.
+
+ --preferred-partition=P preferred partition number, 0 <= P < 255.
+
+ --serial-number=SN setup a new serial number for the hard drive.
+ SN must be non-zero.
+
+ --time-out=T wait T seconds before booting PREVIOUS MBR. if
+ T is 0xff, wait forever. The default is 5.
+
+ --hot-key=K if the desired key K is pressed, start GRUB
+ before booting PREVIOUS MBR. K is a word
+ value, just as the value in AX register
+ returned from int16/AH=1. The high byte is the
+ scan code and the low byte is ASCII code. The
+ default is 0x3920 for space bar. See "int 16
+ keyboard scan codes" below.
+
+ --floppy if DEVICE_OR_FILE is floppy, use this option.
+
+ --floppy=N if DEVICE_OR_FILE is a partition on a hard
+ drive, use this option. N is used to specify
+ the partition number: 0,1,2 and 3 for the
+ primary partitions, and 4,5,6,... for the
+ logical partitions.
+
+ --sectors-per-track=S specifies sectors per track for --floppy.
+ 1 <= S <= 63, default is 63.
+
+ --heads=H specifies number of heads for --floppy.
+ 1 <= H <= 256, default is 255.
+
+ --start-sector=B specifies hidden sectors for --floppy=N.
+
+ --total-sectors=C specifies total sectors for --floppy.
+ default is 0.
+
+ --lba use lba mode for --floppy. If the floppy BIOS
+ has LBA support, you can specify --lba here.
+ It is assumed that all floppy BIOSes have CHS
+ support. So you would rather specify --chs.
+ If neither --chs nor --lba is specified, then
+ the LBA indicator(i.e., the third byte of the
+ boot sector) will not be touched.
+
+ --chs use chs mode for --floppy. You should specify
+ --chs if the floppy BIOS does not support LBA.
+ We assume all floppy BIOSes have CHS support.
+ So it is likely you want to specify --chs.
+ If neither --chs nor --lba is specified, then
+ the LBA indicator(i.e., the third byte of the
+ boot sector) will not be touched.
+
+ --fat12 FAT12 is allowed to be installed for --floppy.
+
+ --fat16 FAT16 is allowed to be installed for --floppy.
+
+ --fat32 FAT32 is allowed to be installed for --floppy.
+
+ --vfat FAT12/16/32 are allowed to be installed for
+ --floppy.
+
+ --ntfs NTFS is allowed to be installed for --floppy.
+
+ --ext2 EXT2 is allowed to be installed for --floppy.
+
+ --install-partition=I Install the boot record onto the boot area of
+ partition number I of the specified hard drive
+ or harddrive image DEVICE_OR_FILE.
+
+DEVICE_OR_FILE: Filename of the device or the image file. For DOS, a BIOS drive
+number(hex 0xHH or decimal DDD) can be used to access the drive. BIOS drive
+number 0 is for the first floppy, 1 is for the second floppy; 0x80 is for the
+first hard drive, 0x81 is for the second hard drive, etc.
+
+Note: BOOTLACE.COM writes only the boot code to MBR. The boot code needs to
+load GRLDR as the second(and last) stage of the GRUB boot process. Therefore
+GRLDR should be copied to the root directory of one of the supported
+partitions, either before or after a successful execution of BOOTLACE.COM.
+Currently only partitions with filesystem type of FAT12, FAT16, FAT32, NTFS,
+EXT2 or EXT3 are supported.
+
+Note 2: If DEVICE_OR_FILE is a harddisk device or a harddisk image file, it
+must contain a valid partition table, otherwise, BOOTLACE.COM will fail. If
+DEVICE_OR_FILE is a floppy device or a floppy image file, then it must contain
+a supported filesystem(i.e., either of FAT12/FAT16/FAT32/NTFS/EXT2/EXT3).
+
+Note 3: If DEVICE_OR_FILE is a floppy device or a floppy image file, and it
+was formated EXT2/EXT3, then you should specify --sectors-per-track and
+--heads explicitly.
+
+
+Important!! If you install GRLDR Boot Record to a floppy or a partition, the
+floppy or partition will boot solely grldr, and your original
+IO.SYS(DOS/Win9x/Me) and NTLDR(WinNT/2K/XP) will become unbootable. This is
+because the original boot record of the floppy or partition was overwritten.
+There is no such problem when installing GRLDR Boot Record onto the MBR.
+Update: Some NTLDR/IO.SYS/KERNEL.SYS files can be directly chainloaded in the
+latest GRUB4DOS.
+
+Tip: If the filename begins in a dash(-) or a digit, you may prefix a dirname
+(./) or (.\) to it.
+
+Examples:
+
+ Installing GRLDR boot code to MBR under Linux:
+
+ bootlace.com /dev/hda
+
+ Installing GRLDR boot code to MBR under DOS:
+
+ bootlace.com 0x80
+
+ Installing GRLDR boot code to a harddisk image under DOS or Linux:
+
+ bootlace.com hd.img
+
+ Installing GRLDR boot code to floppy under Linux:
+
+ bootlace.com --floppy --chs /dev/fd0
+
+ Installing GRLDR boot code to floppy under DOS:
+
+ bootlace.com --floppy --chs 0x00
+
+ Installing GRLDR boot code to a floppy image under DOS or Linux:
+
+ bootlace.com --floppy --chs floppy.img
+
+BOOTLACE.COM cannot function well under Windows NT/2000/XP/2003. It is expected
+(and designed) to run under DOS/Win9x and Linux. Update: For image FILES,
+bootlace.com function well under Windows NT/2000/XP/2003. For devices,
+bootlace.com will not work under Windows NT/2000/XP/2003 because bootlace.com
+is a DOS utility and Windows NT/2000/XP/2003 does not allow bootlace.com to
+access devices.
+
+******************************************************************************
+*** kexec-tools should be patched for the 1.101 release ***
+******************************************************************************
+
+The file kexec-tools-1.101-patch is a patch to the kexec-tools-1.101 release.
+Kexec might fail to load grub.exe without this patch.
+
+The home page of kexec-tools is:
+
+ http://www.xmission.com/~ebiederm/files/kexec/
+
+Note: The Linux kernel should be KEXEC enabled before kexec can be run.
+
+ !! Important Update !!
+
+The patch `kexec-tools-1.101-patch' is not needed now and has been deleted.
+Even worse, it fails in `kexec -l grub.exe --initrd=imgfile'. So please
+do not use it any more.
+
+******************************************************************************
+*** Direct transition to DOS/Win9x from within Linux ***
+******************************************************************************
+
+By using kexec, we can easily boot into DOS/Win9x from a running Linux system.
+
+If WIN98.IMG is a bootable hard-disk image, do as follows:
+
+kexec -l grub.exe --initrd=WIN98.IMG --command-line="--config-file=map (rd) (hd0); map --hook; chainloader (hd0)+1; rootnoverify (hd0)"
+
+kexec -e
+
+If DOS.IMG is a bootable floppy image, do this way:
+
+kexec -l grub.exe --initrd=DOS.IMG --command-line="--config-file=map (rd) (fd0); map --hook; chainloader (fd0)+1; rootnoverify (fd0)"
+
+kexec -e
+
+Note that in this manner, we can boot DOS/Win9x without using a real DOS/Win9x
+disk. We need no FAT partition but an image file.
+
+We have noticed that Linux itself can act as a big boot manager by using kexec
+and grub.exe. This may be convenient to developers who write installation or
+bootstrap or initialization programs.
+
+Certainly, grub.exe and the bootable disk image can also be loaded by a running
+GRUB or LILO or syslinux. Examples:
+
+1. Loaded by GRUB:
+
+ kernel (hd0,0)/grub.exe --config-file="map (rd) (fd0); map --hook; chainloader (fd0)+1; rootnoverify (fd0)"
+ initrd (hd0,0)/DOS.IMG
+ boot
+
+2. Loaded by LILO:
+
+ image=/boot/grub.exe
+ label=grub.exe
+ initrd=/boot/DOS.IMG
+ append="--config-file=map (rd) (fd0); map --hook; chainloader (fd0)+1; rootnoverify (fd0)"
+
+3. Loaded by SYSLINUX:
+
+ label grub.exe
+ kernel grub.exe
+ append initrd=DOS.IMG --config-file="map (rd) (fd0); map --hook; chainloader (fd0)+1; rootnoverify (fd0)"
+
+Note: If the above `map (rd) (...)' failed, you may use `map (rd)+1 (...)'
+instead and try again.
+
+******************************************************************************
+*** Keyboard BIOS Scan Code/ASCII code tables ***
+******************************************************************************
+
+Keyboard bios scan code and ascii character code tables can be obtained from
+the web by, for example, googling for "3920 372A 4A2D 4E2B 352F". Here are 2
+main results:
+
+1. From "http://heim.ifi.uio.no/~stanisls/helppc/scan_codes.html":
+
+INT 16 - Keyboard Scan Codes
+
+ Key Normal Shifted w/Ctrl w/Alt
+
+ A 1E61 1E41 1E01 1E00
+ B 3062 3042 3002 3000
+ C 2E63 2E43 2E03 2E00
+ D 2064 2044 2004 2000
+ E 1265 1245 1205 1200
+ F 2166 2146 2106 2100
+ G 2267 2247 2207 2200
+ H 2368 2348 2308 2300
+ I 1769 1749 1709 1700
+ J 246A 244A 240A 2400
+ K 256B 254B 250B 2500
+ L 266C 264C 260C 2600
+ M 326D 324D 320D 3200
+ N 316E 314E 310E 3100
+ O 186F 184F 180F 1800
+ P 1970 1950 1910 1900
+ Q 1071 1051 1011 1000
+ R 1372 1352 1312 1300
+ S 1F73 1F53 1F13 1F00
+ T 1474 1454 1414 1400
+ U 1675 1655 1615 1600
+ V 2F76 2F56 2F16 2F00
+ W 1177 1157 1117 1100
+ X 2D78 2D58 2D18 2D00
+ Y 1579 1559 1519 1500
+ Z 2C7A 2C5A 2C1A 2C00
+
+ Key Normal Shifted w/Ctrl w/Alt
+
+ 1 0231 0221 7800
+ 2 0332 0340 0300 7900
+ 3 0433 0423 7A00
+ 4 0534 0524 7B00
+ 5 0635 0625 7C00
+ 6 0736 075E 071E 7D00
+ 7 0837 0826 7E00
+ 8 0938 092A 7F00
+ 9 0A39 0A28 8000
+ 0 0B30 0B29 8100
+
+ Key Normal Shifted w/Ctrl w/Alt
+
+ - 0C2D 0C5F 0C1F 8200
+ = 0D3D 0D2B 8300
+ [ 1A5B 1A7B 1A1B 1A00
+ ] 1B5D 1B7D 1B1D 1B00
+ ; 273B 273A 2700
+ ' 2827 2822
+ ` 2960 297E
+ \ 2B5C 2B7C 2B1C 2600 (same as Alt L)
+ , 332C 333C
+ . 342E 343E
+ / 352F 353F
+
+ Key Normal Shifted w/Ctrl w/Alt
+
+ F1 3B00 5400 5E00 6800
+ F2 3C00 5500 5F00 6900
+ F3 3D00 5600 6000 6A00
+ F4 3E00 5700 6100 6B00
+ F5 3F00 5800 6200 6C00
+ F6 4000 5900 6300 6D00
+ F7 4100 5A00 6400 6E00
+ F8 4200 5B00 6500 6F00
+ F9 4300 5C00 6600 7000
+ F10 4400 5D00 6700 7100
+ F11 8500 8700 8900 8B00
+ F12 8600 8800 8A00 8C00
+
+ Key Normal Shifted w/Ctrl w/Alt
+
+ BackSpace 0E08 0E08 0E7F 0E00
+ Del 5300 532E 9300 A300
+ Down Arrow 5000 5032 9100 A000
+ End 4F00 4F31 7500 9F00
+ Enter 1C0D 1C0D 1C0A A600
+ Esc 011B 011B 011B 0100
+ Home 4700 4737 7700 9700
+ Ins 5200 5230 9200 A200
+ Keypad 5 4C35 8F00
+ Keypad * 372A 9600 3700
+ Keypad - 4A2D 4A2D 8E00 4A00
+ Keypad + 4E2B 4E2B 4E00
+ Keypad / 352F 352F 9500 A400
+ Left Arrow 4B00 4B34 7300 9B00
+ PgDn 5100 5133 7600 A100
+ PgUp 4900 4939 8400 9900
+ PrtSc 7200
+ Right Arrow 4D00 4D36 7400 9D00
+ SpaceBar 3920 3920 3920 3920
+ Tab 0F09 0F00 9400 A500
+ Up Arrow 4800 4838 8D00 9800
+
+
+- Some key combinations are not available on all systems. The PS/2
+ includes many that aren't available on the PC, XT and AT.
+- To retrieve the character from a scan code logical AND the word
+ with 0x00FF.
+- see INT 16 MAKE CODES
+
+
+
+2. From "http://www.hoppie.nl/ivan/keycodes.txt":
+
+
+
+ Keystroke Keypress code
+--------------------------------------------------
+ Esc 011B
+ 1 0231
+ 2 0332
+ 3 0433
+ 4 0534
+ 5 0635
+ 6 0736
+ 7 0837
+ 8 0938
+ 9 0A39
+ 0 0B30
+ - 0C2D
+ = 0D3D
+ Backspace 0E08
+ Tab 0F09
+ q 1071
+ w 1177
+ e 1265
+ r 1372
+ t 1474
+ y 1579
+ u 1675
+ i 1769
+ o 186F
+ p 1970
+ [ 1A5B
+ ] 1B5D
+ Enter 1C0D
+ Ctrl **
+ a 1E61
+ s 1F73
+ d 2064
+ f 2166
+ g 2267
+ h 2368
+ j 246A
+ k 256B
+ l 266C
+ ; 273B
+ ' 2827
+ ` 2960
+ Shift **
+ \ 2B5C
+ z 2C7A
+ x 2D78
+ c 2E63
+ v 2F76
+ b 3062
+ n 316E
+ m 326D
+ , 332C
+ . 342E
+ / 352F
+ Gray * 372A
+ Alt **
+ Space 3920
+ Caps Lock **
+ F1 3B00
+ F2 3C00
+ F3 3D00
+ F4 3E00
+ F5 3F00
+ F6 4000
+ F7 4100
+ F8 4200
+ F9 4300
+ F10 4400
+ F11 8500
+ F12 8600
+ Num Lock **
+ Scroll Lock **
+ White Home 4700
+ White Up Arrow 4800
+ White PgUp 4900
+ Gray - 4A2D
+ White Left Arrow 4B00
+ Center Key 4C00
+ White Right Arrow 4D00
+ Gray + 4E2B
+ White End 4F00
+ White Down Arrow 5000
+ White PgDn 5100
+ White Ins 5200
+ White Del 5300
+ SysReq **
+ Key 45 [1] 565C
+ Enter (number keypad) 1C0D
+ Gray / 352F
+ PrtSc **
+ Pause **
+ Gray Home 4700
+ Gray Up Arrow 4800
+ Gray Page Up 4900
+ Gray Left Arrow 4B00
+ Gray Right Arrow 4D00
+ Gray End 4F00
+ Gray Down Arrow 5000
+ Gray Page Down 5100
+ Gray Insert 5200
+ Gray Delete 5300
+
+ Shift Esc 011B
+ ! 0221
+ @ 0340
+ # 0423
+ $ 0524
+ % 0625
+ ^ 075E
+ & 0826
+ * (white) 092A
+ ( 0A28
+ ) 0B29
+ _ 0C5F
+ + (white) 0D2B
+ Shift Backspace 0E08
+ Shift Tab (Backtab) 0F00
+ Q 1051
+ W 1157
+ E 1245
+ R 1352
+ T 1454
+ Y 1559
+ U 1655
+ I 1749
+ O 184F
+ P 1950
+ { 1A7B
+ } 1B7D
+ Shift Enter 1C0D
+ Shift Ctrl **
+ A 1E41
+ S 1F53
+ D 2044
+ F 2146
+ G 2247
+ H 2348
+ J 244A
+ K 254B
+ L 264C
+ : 273A
+ " 2822
+ ~ 297E
+ | 2B7C
+ Z 2C5A
+ X 2D58
+ C 2E43
+ V 2F56
+ B 3042
+ N 314E
+ M 324D
+ < 333C
+ > 343E
+ ? 353F
+ Shift Gray * 372A
+ Shift Alt **
+ Shift Space 3920
+ Shift Caps Lock **
+ Shift F1 5400
+ Shift F2 5500
+ Shift F3 5600
+ Shift F4 5700
+ Shift F5 5800
+ Shift F6 5900
+ Shift F7 5A00
+ Shift F8 5B00
+ Shift F9 5C00
+ Shift F10 5D00
+ Shift F11 8700
+ Shift F12 8800
+ Shift Num Lock **
+ Shift Scroll Lock **
+ Shift 7 (number pad) 4737
+ Shift 8 (number pad) 4838
+ Shift 9 (number pad) 4939
+ Shift Gray - 4A2D
+ Shift 4 (number pad) 4B34
+ Shift 5 (number pad) 4C35
+ Shift 6 (number pad) 4D36
+ Shift Gray + 4E2B
+ Shift 1 (number pad) 4F31
+ Shift 2 (number pad) 5032
+ Shift 3 (number pad) 5133
+ Shift 0 (number pad) 5230
+ Shift . (number pad) 532E
+ Shift SysReq **
+ Shift Key 45 [1] 567C
+ Shift Enter (number pad) 1C0D
+ Shift Gray / 352F
+ Shift PrtSc **
+ Shift Pause **
+ Shift Gray Home 4700
+ Shift Gray Up Arrow 4800
+ Shift Gray Page Up 4900
+ Shift Gray Left Arrow 4B00
+ Shift Gray Right Arrow 4D00
+ Shift Gray End 4F00
+ Shift Gray Down Arrow 5000
+ Shift Gray Page Down 5100
+ Shift Gray Insert 5200
+ Shift Gray Delete 5300
+
+ Ctrl Esc 011B
+ Ctrl 1 --
+ Ctrl 2 (NUL) 0300
+ Ctrl 3 --
+ Ctrl 4 --
+ Ctrl 5 --
+ Ctrl 6 (RS) 071E
+ Ctrl 7 --
+ Ctrl 8 --
+ Ctrl 9 --
+ Ctrl 0 --
+ Ctrl - 0C1F
+ Ctrl = --
+ Ctrl Backspace (DEL) 0E7F
+ Ctrl Tab 9400
+ Ctrl q (DC1) 1011
+ Ctrl w (ETB) 1117
+ Ctrl e (ENQ) 1205
+ Ctrl r (DC2) 1312
+ Ctrl t (DC4) 1414
+ Ctrl y (EM) 1519
+ Ctrl u (NAK) 1615
+ Ctrl i (HT) 1709
+ Ctrl o (SI) 180F
+ Ctrl p (DEL) 1910
+ Ctrl [ (ESC) 1A1B
+ Ctrl ] (GS) 1B1D
+ Ctrl Enter (LF) 1C0A
+ Ctrl a (SOH) 1E01
+ Ctrl s (DC3) 1F13
+ Ctrl d (EOT) 2004
+ Ctrl f (ACK) 2106
+ Ctrl g (BEL) 2207
+ Ctrl h (Backspace) 2308
+ Ctrl j (LF) 240A
+ Ctrl k (VT) 250B
+ Ctrl l (FF) 260C
+ Ctrl ; --
+ Ctrl ' --
+ Ctrl ` --
+ Ctrl Shift **
+ Ctrl \ (FS) 2B1C
+ Ctrl z (SUB) 2C1A
+ Ctrl x (CAN) 2D18
+ Ctrl c (ETX) 2E03
+ Ctrl v (SYN) 2F16
+ Ctrl b (STX) 3002
+ Ctrl n (SO) 310E
+ Ctrl m (CR) 320D
+ Ctrl , --
+ Ctrl . --
+ Ctrl / --
+ Ctrl Gray * 9600
+ Ctrl Alt **
+ Ctrl Space 3920
+ Ctrl Caps Lock --
+ Ctrl F1 5E00
+ Ctrl F2 5F00
+ Ctrl F3 6000
+ Ctrl F4 6100
+ Ctrl F5 6200
+ Ctrl F6 6300
+ Ctrl F7 6400
+ Ctrl F8 6500
+ Ctrl F9 6600
+ Ctrl F10 6700
+ Ctrl F11 8900
+ Ctrl F12 8A00
+ Ctrl Num Lock --
+ Ctrl Scroll Lock --
+ Ctrl White Home 7700
+ Ctrl White Up Arrow 8D00
+ Ctrl White PgUp 8400
+ Ctrl Gray - 8E00
+ Ctrl White Left Arrow 7300
+ Ctrl 5 (number pad) 8F00
+ Ctrl White Right Arrow 7400
+ Ctrl Gray + 9000
+ Ctrl White End 7500
+ Ctrl White Down Arrow 9100
+ Ctrl White PgDn 7600
+ Ctrl White Ins 9200
+ Ctrl White Del 9300
+ Ctrl SysReq **
+ Ctrl Key 45 [1] --
+ Ctrl Enter (number pad) 1C0A
+ Ctrl / (number pad) 9500
+ Ctrl PrtSc 7200
+ Ctrl Break 0000
+ Ctrl Gray Home 7700
+ Ctrl Gray Up Arrow 8DE0
+ Ctrl Gray Page Up 8400
+ Ctrl Gray Left Arrow 7300
+ Ctrl Gray Right Arrow 7400
+ Ctrl Gray End 7500
+ Ctrl Gray Down Arrow 91E0
+ Ctrl Gray Page Down 7600
+ Ctrl Gray Insert 92E0
+ Ctrl Gray Delete 93E0
+
+ Alt Esc 0100
+ Alt 1 7800
+ Alt 2 7900
+ Alt 3 7A00
+ Alt 4 7B00
+ Alt 5 7C00
+ Alt 6 7D00
+ Alt 7 7E00
+ Alt 8 7F00
+ Alt 9 8000
+ Alt 0 8100
+ Alt - 8200
+ Alt = 8300
+ Alt Backspace 0E00
+ Alt Tab A500
+ Alt q 1000
+ Alt w 1100
+ Alt e 1200
+ Alt r 1300
+ Alt t 1400
+ Alt y 1500
+ Alt u 1600
+ Alt i 1700
+ Alt o 1800
+ Alt p 1900
+ Alt [ 1A00
+ Alt ] 1B00
+ Alt Enter 1C00
+ Alt Ctrl **
+ Alt a 1E00
+ Alt s 1F00
+ Alt d 2000
+ Alt f 2100
+ Alt g 2200
+ Alt h 2300
+ Alt j 2400
+ Alt k 2500
+ Alt l 2600
+ Alt ; 2700
+ Alt ' 2800
+ Alt ` 2900
+ Alt Shift **
+ Alt \ 2B00
+ Alt z 2C00
+ Alt x 2D00
+ Alt c 2E00
+ Alt v 2F00
+ Alt b 3000
+ Alt n 3100
+ Alt m 3200
+ Alt , 3300
+ Alt . 3400
+ Alt / 3500
+ Alt Gray * 3700
+ Alt Space 3920
+ Alt Caps Lock **
+ Alt F1 6800
+ Alt F2 6900
+ Alt F3 6A00
+ Alt F4 6B00
+ Alt F5 6C00
+ Alt F6 6D00
+ Alt F7 6E00
+ Alt F8 6F00
+ Alt F9 7000
+ Alt F10 7100
+ Alt F11 8B00
+ Alt F12 8C00
+ Alt Num Lock **
+ Alt Scroll Lock **
+ Alt Gray - 4A00
+ Alt Gray + 4E00
+ Alt 7 (number pad) #
+ Alt 8 (number pad) #
+ Alt 9 (number pad) #
+ Alt 4 (number pad) #
+ Alt 5 (number pad) #
+ Alt 6 (number pad) #
+ Alt 1 (number pad) #
+ Alt 2 (number pad) #
+ Alt 3 (number pad) #
+ Alt Del --
+ Alt SysReq **
+ Alt Key 45 [1] --
+ Alt Enter (number pad) A600
+ Alt / (number pad) A400
+ Alt PrtSc **
+ Alt Pause **
+ Alt Gray Home 9700
+ Alt Gray Up Arrow 9800
+ Alt Gray Page Up 9900
+ Alt Gray Left Arrow 9B00
+ Alt Gray Right Arrow 9D00
+ Alt Gray End 9F00
+ Alt Gray Down Arrow A000
+ Alt Gray Page Down A100
+ Alt Gray Insert A200
+ Alt Gray Delete A300
+
+ -------------------------------------------------------------------------
+
+Footnotes
+
+ [1] In the United States, the 101/102-key keyboard is shipped
+ with 101 keys. Overseas versions have an additional key
+ sandwiched between the left Shift key and the Z key. This
+ additional key is identified by IBM (and in this table) as
+ "Key 45."
+
+ [**] Keys and key combinations marked ** are used by the ROM BIOS
+ but do not put values into the keyboard buffer.
+
+ [--] Keys and key combinations marked -- are ignored by the ROM
+ BIOS.
+
+
+
+
+3. From "http://heim.ifi.uio.no/~stanisls/helppc/make_codes.html":
+
+
+INT 9 - Hardware Keyboard Make/Break Codes
+
+ Key Make Break Key Make Break
+
+ Backspace 0E 8E F1 3B BB
+ Caps Lock 3A BA F2 3C BC
+ Enter 1C 9C F3 3D BD
+ Esc 01 81 F4 3E BE
+ Left Alt 38 B8 F7 41 C1
+ Left Ctrl 1D 9D F5 3F BF
+ Left Shift 2A AA F6 40 C0
+ Num Lock 45 C5 F8 42 C2
+ Right Shift 36 B6 F9 43 C3
+ Scroll Lock 46 C6 F10 44 C4
+ Space 39 B9 F11 57 D7
+ Sys Req (AT) 54 D4 F12 58 D8
+ Tab 0F 8F
+
+ Keypad Keys Make Break
+
+ Keypad 0 (Ins) 52 D2
+ Keypad 1 (End) 4F CF
+ Keypad 2 (Down arrow) 50 D0
+ Keypad 3 (PgDn) 51 D1
+ Keypad 4 (Left arrow) 4B CB
+ Keypad 5 4C CC
+ Keypad 6 (Right arrow) 4D CD
+ Keypad 7 (Home) 47 C7
+ Keypad 8 (Up arrow) 48 C8
+ Keypad 9 (PgUp) 49 C9
+ Keypad . (Del) 53 D3
+ Keypad * (PrtSc) 37 B7
+ Keypad - 4A CA
+ Keypad + 4E CE
+
+ Key Make Break Key Make Break
+
+ A 1E 9E N 31 B1
+ B 30 B0 O 18 98
+ C 2E AE P 19 99
+ D 20 A0 Q 10 90
+ E 12 92 R 13 93
+ F 21 A1 S 1F 9F
+ G 22 A2 T 14 94
+ H 23 A3 U 16 96
+ I 17 97 V 2F AF
+ J 24 A4 W 11 91
+ K 25 A5 X 2D AD
+ L 26 A6 Y 15 95
+ M 32 B2 Z 2C AC
+
+ Key Make Break Key Make Break
+
+ 1 02 82 - 0C 8C
+ 2 03 83 = 0D 8D
+ 3 04 84 [ 1A 9A
+ 4 05 85 ] 1B 9B
+ 5 06 86 ; 27 A7
+ 6 07 87 ' 28 A8
+ 7 08 88 ` 29 A9
+ 8 09 89 \ 2B AB
+ 9 0A 8A , 33 B3
+ 0 0B 8B . 34 B4
+ / 35 B5
+
+
+Enhanced Keyboard Keys (101/102 keys)
+
+ Control Keys Make Break
+
+ Alt-PrtSc (SysReq) 54 D4
+ Ctrl-PrtSc E0 37 E0 B7
+ Enter E0 1C E0 9C
+ PrtSc E0 2A E0 37 E0 B7 E0 AA
+ Right Alt E0 38 E0 B8
+ Right Ctrl E0 1D E0 9D
+ Shift-PrtSc E0 37 E0 B7
+ / E0 35 E0 B5
+ Pause E1 1D 45 E1 9D C5 (not typematic)
+ Ctrl-Pause (Ctrl-Break) E0 46 E0 C6 (not typematic)
+
+ - Keys marked as "not typematic" generate one stream of bytes
+ without corresponding break scan code bytes (actually the
+ break codes are part of the make code).
+
+
+ Normal Mode or
+ Shift w/Numlock
+ Key Make Break |----- Numlock on ------.
+ Make Break
+ Del E0 53 E0 D3 E0 2A E0 53 E0 D3 E0 AA
+ Down arrow E0 50 E0 D0 E0 2A E0 50 E0 D0 E0 AA
+ End E0 4F E0 CF E0 2A E0 4F E0 CF E0 AA
+ Home E0 47 E0 C7 E0 2A E0 47 E0 C7 E0 AA
+ Ins E0 52 E0 D2 E0 2A E0 52 E0 D2 E0 AA
+ Left arrow E0 4B E0 CB E0 2A E0 4B E0 CB E0 AA
+ PgDn E0 51 E0 D1 E0 2A E0 51 E0 D1 E0 AA
+ PgUp E0 49 E0 C9 E0 2A E0 49 E0 C9 E0 AA
+ Right arrow E0 4D E0 CD E0 2A E0 4D E0 CD E0 AA
+ Up arrow E0 48 E0 C8 E0 2A E0 48 E0 C8 E0 AA
+
+ Key |--Left Shift Pressed--. |--Right Shift Pressed--.
+ Make Break Make Break
+ Del E0 AA E0 53 E0 D3 E0 2A E0 B6 E0 53 E0 D3 E0 36
+ Down arrow E0 AA E0 50 E0 D0 E0 2A E0 B6 E0 50 E0 D0 E0 36
+ End E0 AA E0 4F E0 CF E0 2A E0 B6 E0 4F E0 CF E0 36
+ Home E0 AA E0 47 E0 C7 E0 2A E0 B6 E0 47 E0 C7 E0 36
+ Ins E0 AA E0 52 E0 D2 E0 2A E0 B6 E0 52 E0 D2 E0 36
+ Left arrow E0 AA E0 4B E0 CB E0 2A E0 B6 E0 4B E0 CB E0 36
+ PgDn E0 AA E0 51 E0 D1 E0 2A E0 B6 E0 51 E0 D1 E0 36
+ PgUp E0 AA E0 49 E0 C9 E0 2A E0 B6 E0 49 E0 C9 E0 36
+ Right arrow E0 AA E0 4D E0 CD E0 2A E0 B6 E0 4D E0 CD E0 36
+ Up arrow E0 AA E0 48 E0 C8 E0 2A E0 B6 E0 48 E0 C8 E0 36
+ / E0 AA E0 35 E0 B5 E0 2A E0 B6 E0 35 E0 B5 E0 36
+
+
+ - The PS/2 models have three make/break scan code sets. The first
+ set matches the PC & XT make/break scan code set and is the one
+ listed here. Scan code sets are selected by writing the value F0
+ to the keyboard via the 8042 (port 60h). The following is a brief
+ description of the scan code sets (see the PS/2 Technical Reference
+ manuals for more information on scan code sets 2 and 3):
+
+ / set 1, each key has a base scan code. Some keys generate
+ extra scan codes to generate artificial shift states. This
+ is similar to the standard scan code set used on the PC and XT.
+ / set 2, each key sends one make scan code and two break scan
+ codes bytes (F0 followed by the make code). This scan code
+ set is available on the IBM AT also.
+ / set 3, each key sends one make scan code and two break scan
+ codes bytes (F0 followed by the make code) and no keys are
+ altered by Shift/Alt/Ctrl keys.
+ / typematic scan codes are the same as the make scan code
+
+ - Some Tandy 1000's do not handle Alt key combinations when multiple
+ shift keys are pressed. The Alt-Shift-H combination loses the Alt.
+ - extended keys like (F11, F12) can only be read with systems that
+ have extended keyboard BIOS support (or INT 9 extensions); to
+ read these special keys on these systems INT 16,10 must be used
+
+
+******************************************************************************
+*** GRLDR Error messages ***
+******************************************************************************
+
+1. Missing MBR-helper.
+
+ The helper function in the sectors that immediately follow the MBR is
+ not present, or it has been erased by a virus or by Windows XP/Vista.
+
+ Run the bootlace.com utility to fix the problem.
+
+2. Buggy BIOS!
+
+ Your BIOS is too buggy. It even has no support for INT13/AH=8.
+
+ No solution except flashing your BIOS. Buggy BIOSes will encounter
+ more and more problems with grub4dos in the future.
+
+3. This partition is NTFS but with unknown boot record. Please install
+Microsoft NTFS boot sectors to this partition correctly, or create an
+FAT12/16/32 partition and place the same copy of GRLDR and MENU.LST there.
+
+ The boot record was changed or erased by Microsoft Windows XP Service
+ Pack 2.
+
+ You may install the old boot record introduced with the original clean
+ Windows 2K/XP. As another solution, you may create an FAT partition
+ for your system, and copy GRLDR and your MENU.LST to its root dir.
+
+ While the startup code of grldr might fail to load GRLDR in NTFS
+ partitions, it always successfully loads GRLDR in FAT partitions(and
+ even in ext2/ext3 partitions).
+
+ Note that NTLDR only loads the startup code of grldr(i.e., the leading
+ 16 sectors of grldr), not the whole grldr file.
+
+ Thus, C:\GRLDR must exist(here C: can be NTFS), since it is used for
+ BOOT.INI and NTLDR. If C: is NTFS, X:\GRLDR should exist as well,
+ where X: stands for a certain FAT partition.
+
+
+******************************************************************************
+*** Known BIOS bugs ***
+******************************************************************************
+
+1. Some newer Dell machines have no int13/AH=43h support. You may encounter
+ failure when trying to write-access an emulated disk.
+
+ Note: This bug is serious! The old "root+setup" installation method
+ (in real mode grub environment) uses INT13 to write the first sector
+ of stage2. It will fail for the buggy DELL machine when stage2 is
+ accessed with LBA mode.
+
+2. Some buggy BIOSes won't boot bootable.iso(See above).(qemu can boot it fine)
+
+3. Some newer Dell machines violently destroyed the interrupt vectors for
+ hardware IRQs and will hang the machine when running GRUB.EXE
+ from DOS. You may try again with BADGRUB.EXE.
+
+4. Reports say some BIOSes will function abnormally after GRUB.EXE is started
+ by kexec of Linux. Some machines reportedly hang. Some others
+ reportedly cannot access USB drives.
+
+
+******************************************************************************
+*** Known Problems ***
+******************************************************************************
+
+1. Running GRUB.EXE from a DOS box of Windows 9x/Me could hang the
+ machine, especially for some systems with USB support. You may
+ encounter the same problem when running GRUB.EXE through KEXEC under
+ Linux.
+
+Note: You don't have to run GRUB.EXE from protected mode of Win9x, which
+ could hang the machine; Instead, you usually want to run GRUB.EXE
+ after you have done a "Restart the computer in MS-DOS mode", which
+ is safe enough.
+
+2. The default chainloader action will keep A20 on. Some buggy DOS XMS
+ memory managers could hang the machine. You may use the --disable-a20
+ option in the chainloader line and try again. Anyway, you should avoid
+ using those buggy memory managers.
+
+3. THTF BIOS L4S5M Ver 1.1a(dated 2002-1-10) has a buggy int15 which
+ causes hang at the boot of a multi boot kernel(memdisk for example).
+
+4. A Chinese DOS system software, the TechWay SCS, will not work with
+ newer versions of GRUB.EXE. In general, TSRs that take antitracking
+ measures will not work with GRUB.EXE any more.
+
+
+******************************************************************************
+*** List of binary files and their corresponding source files ***
+******************************************************************************
+
+binary file main source file other included source or binary files
+------------- ---------------- -------------------------------------
+
+bootlace.com bootlacestart.S bootlace.inc, grldrstart.S
+
+grldr grldrstart.S pre_stage2(binary, See note below)
+
+grldr.mbr mbrstart.S grldrstart.S
+
+grub.exe dosstart.S pre_stage2(binary, See note below)
+
+hmload.com hmloadstart.S
+
+-----------------------------------------------------------------------------
+
+Note: pre_stage2 is the main body of GNU GRUB and it is simply appended to
+grldrstart/dosstart in binary format to form our grldr/grub.exe.
+
+Note: The GRUB file(WITHOUT .EXE suffix) is a static-linked ELF executable
+program for Linux, normally called the GRUB Shell. The GRUB Shell is a boot-
+manager, but not a boot-loader(the "boot" command won't work in GRUB Shell).
+GRUB.EXE(with KEXEC) can be used as a bootloader running directly under Linux.
+
+******************************************************************************
+*** Memory Layout for Quiting to DOS from GRUB.EXE ***
+******************************************************************************
+
+The quit command is implemented to return to DOS in the instance that GRUB.EXE
+is started off DOS.
+
+1. Before GRUB.EXE transfers control to pre_stage2, it will copy 640KB of
+conventional memory to physical address 0x200000(i.e., 2MB), and write 4 long
+integers immediately follows the backup copy of the conventional memory:
+ At 0x2A0000: 0x50554B42, it is the "BKUP" signature.
+
+ At 0x2A0004: Gate A20 status under DOS: non-zero means A20 on;
+ zero means A20 off. Update: A20 always on, see below.
+
+ At 0x2A0008: high word is boot-CS, low word is boot-IP. The quit
+ command uses this entry point to return to DOS.
+
+ At 0x2A000C: CheckSum: the sum of all long integers in the memory
+ range from 0x200000 to 0x2A000F is 0.
+
+2. If the above memory structure is corrupted by a grub command, the quit
+command will issue an error message and refuse to exit from grub.
+
+3. Because GRUB may corrupt extended memory, you should better avoid using
+extended memory under DOS before running GRUB.EXE.
+
+4. Gate A20 will be enabled by GRUB.EXE. Hopefully this would hurt nothing.
+
+
+******************************************************************************
+*** Memory usage in conventional/low memory area ***
+******************************************************************************
+
+1. boot.c, fsys_reiserfs.c: 8K below 0x68000.
+
+2. fsys_ext2fs.c, fsys_minix.c: 1K below 0x68000.
+
+3. fsys_jfs.c: 4K + 256 bytes below 0x68000.
+
+4. fsys_reiserfs.c: 202 bytes at 0x600.
+
+5. fsys_xfs.c: 188 bytes at 0x600.
+
+6. fsys_xfs.c: (logical block size) bytes below 0x68000.
+
+7. geometry tune: 0x50000 - 0x5ffff.
+
+******************************************************************************
+*** Command-line Length about GRUB.EXE ***
+******************************************************************************
+
+GRUB.EXE now can be started in CONFIG.SYS with the **DEVICE** command:
+
+ DEVICE=grub.exe [--config-file="FILENAME_OR_COMMANDS"]
+
+1. If GRUB.EXE is invoked with DEVICE command and FILENAME_OR_COMMANDS is a
+collection of some GRUB commands separated by semi-colon, then the length of
+FILENAME_OR_COMMANDS can be nearly 4KB ----Supprise? But true! MS-DOS 7+
+even allows a much longer line, but 4KB seems enough for our use of GRUB.EXE.
+This is very useful when we want to embed a big menu into the command line.
+Note that GRLDR hasn't yet supported any command-line arguments.
+
+2. If GRUB.EXE is invoked with INSTALL command, the option length has a limit
+of 80 characters(including the leading "--config-file=" part). An overflow may
+hang up MS-DOS immediately.
+
+3. If GRUB.EXE is invoked with SHELL command, the option length has a limit of
+126 characters(including the leading "--config-file=" part). Overflow won't
+hang up MS-DOS, but the line will be cut short. This limit is the same as that
+in the console-DOS-prompt or in a BAT file.
+
+4. The DOS editor EDIT does not allow to create a line of 4KB long. So use
+another editor, for example, vi for Linux, please.
+
+5. The DEVICE=GRUB.EXE line can be used together with other DEVICE commands
+such as DEVICE=HIMEM.SYS and DEVICE=EMM386.EXE. The GRUB.EXE line should
+occur before the EMM386.EXE line in order to avoid the rejection by EMM386.
+Update: Since 0.4.2, GRUB.EXE works well even after EMM386.EXE is loaded.
+
+6. In any case mentioned above, you can return back to DOS by quit command.
+
+7. Memory usage about command-line menu: The 4KB command-line menu starts at
+physical address 0x0800 and ends at 0x17FF.
+
+******************************************************************************
+*** New Syntax for the DEFAULT/SAVEDEFAULT Commands ***
+******************************************************************************
+
+In addition to the original usage of "default NUM" and "default saved", now
+there is a new usage of "default FILE", like this:
+
+ default (hd0,0)/default
+
+Note that FILE must have a valid DEFAULT file format. A sample DEFAULT file
+is included in the release. You may copy it to wherever you like, but you
+should avoid modifying its content manually. The DEFAULT file may be used
+in this way:
+
+(1) First, you should copy a default file with valid format to somewhere in
+your operating system.
+
+(2) Secondly, you should use the "default FILE" command of GRUB to announce
+the use of FILE as our new default file for being written by "savedefault".
+
+(3) Then, you may use "savedefault" command to save the desired entry number
+into this new default file.
+
+(4) OK, at next boot, you may read the saved entry number by using the same
+"default FILE" command as mentioned in above (2).
+
+And the SAVEDEFAULT command now accept an options `--wait=T', like this:
+
+ savedefault --wait=5
+
+If `--wait=T' is specified and T is non-zero, savedefault will prompt
+the user with a message just before it writes to disk. The write operation
+will be cancelled in T seconds if the `Y' key was not pressed.
+
+Here is a sample menu.lst file:
+
+#--------------------begin menu.lst---------------------------------------
+color black/cyan yellow/cyan
+timeout 30
+default /default
+
+title find and load NTLDR of Windows NT/2K/XP
+find --set-root /ntldr
+chainloader /ntldr
+savedefault --wait=2
+
+title find and load CMLDR, the Recovery Console of Windows NT/2K/XP
+fallback 2
+find --set-root /cmldr
+chainloader /cmldr
+#####################################################################
+# write string "cmdcons" to memory 0000:7C03 in 2 steps:
+#####################################################################
+# step 1. Write 4 chars "cmdc" at 0000:7C03
+write 0x7C03 0x63646D63
+# step 2. Write 3 chars "ons" and an ending null at 0000:7C07
+write 0x7C07 0x00736E6F
+savedefault --wait=2
+
+title find and load IO.SYS of Windows 9x/Me
+find --set-root /io.sys
+chainloader /io.sys
+savedefault --wait=2
+
+title floppy (fd0)
+chainloader (fd0)+1
+rootnoverify (fd0)
+savedefault --wait=2
+
+title find and boot Linux with menu.lst already installed
+find --set-root /sbin/init
+savedefault --wait=2
+configfile /boot/grub/menu.lst
+
+title find and boot Mandriva with menu.lst already installed
+find --set-root /etc/mandriva-release
+savedefault --wait=2
+configfile /boot/grub/menu.lst
+
+title back to dos
+savedefault --wait=2
+quit
+
+title commandline
+savedefault --wait=2
+commandline
+
+title reboot
+savedefault --wait=2
+reboot
+
+title halt
+savedefault --wait=2
+halt
+#--------------------end menu.lst---------------------------------------
+
+Note 1: The file DEFAULT must exist and have a proper format as stated above.
+ Or else, the default/savedefault commands won't function well.
+
+Note 2: The file DEFAULT which is in the same dir as a certain MENU.LST file
+ is called associated with the MENU.LST file.
+
+Note 3: The associated DEFAULT file will take effect automatically if there
+ are no `default' commands present.
+
+Note 4: Just before a menu file gains control(e.g., it is the associated
+ MENU.LST of a GRLDR file, or it was specified via
+ `grub.exe --config-file=(DEVICE)/PATH/YOUR_MENU_FILE', or it was
+ specified by the `configfile' command of grub), its associated
+ DEFAULT file will be used if present, until an explicit `default'
+ command is encountered.
+
+******************************************************************************
+*** The New `cdrom' Command Syntax ***
+******************************************************************************
+
+1. Initialize the ATAPI CDROM devices:
+
+ grub> cdrom --init
+
+ This will display the number of atapi cdroms found: atapi_dev_count
+
+2. Stop the ATAPI CDROM devices:
+
+ grub> cdrom --stop
+
+ This will set atapi_dev_count to 0.
+
+3. Add IO ports for searching the atapi cdrom devices. For example:
+
+ grub> cdrom --add-io-ports=0x03F601F0
+
+After running `cdrom --init' and `map --hook', the cdroms can be accessed
+through devices (cd0), (cd1), ...
+
+Note 1: If the system does not fully support the ATAPI CD-ROM specifications,
+ you will encounter failure when trying to access the (cdX) devices.
+
+Note 2: After doing a `cdrom --stop', you should do a `map --unhook'. Of
+ course you may `map --hook' again if there are mapped drives.
+
+Note 3: After adding IO ports, you should do a `map --unhook' followed by a
+ `cdrom --init' and then followed by a `map --hook'.
+
+ By default, these ports are used for searching cdroms(so they needn't
+ be added):
+
+ 0x03F601F0, 0x03760170, 0x02F600F0,
+ 0x03860180, 0x6F006B00, 0x77007300.
+
+Note 4: The BIOS might have offered a cdrom interface. It would be (cd). After
+ `cdrom --init' and `map --hook', we might have our (cd0), (cd1), ...
+ available. It is likely that one of them could access the same media
+ as the BIOS-offered (cd).
+
+Note 5: You may access the (cd) and (cdX)'es in the blocklist way. Example:
+
+ cat --hex (cd0)16+2
+
+ The cdrom sectors are big sectors with a size of 2048 bytes.
+
+Note 6: The iso9660 filesystem driver has Rock-Ridge extension support, but
+ has no Joliet extension support. So you may encounter failure when
+ you attempt to read files on a Joliet CD.
+
+Note 7: The (cd) or (cdX)'es can be booted now. Examples:
+
+ chainloader (cd)
+ boot
+
+ chainloader (cd0)
+ boot
+
+ chainloader (cd1)
+ boot
+
+ You should already have access to the CD sectors before you can
+ chainload it.
+
+******************************************************************************
+*** About the New `setvbe' Command ***
+******************************************************************************
+
+Gerardo Richarte contributed the `setvbe' code and the following comment:
+
+ New command is `setvbe', and can be used to change the video mode
+ before executing the kernel.
+
+ For example, you can do
+
+ setvbe 1024x768x32
+
+ this will scan the list of available modes and set it, and
+ automatically append a `video=' option to each subsequent kernel
+ command-line. The appended `video=' option is like this:
+
+ video=1024x768x32@0xf0000000,4096
+
+ where 0xf0000000 is the video framebuffer address as reported by vbe,
+ and 4096 is the size of a scanline in bytes (also as reported by vbe).
+
+ This is really useful if you want to give some graphics support to your
+ OS, but you don't want to implement any video functionality other than
+ writing a pixel to video memory.
+
+
+******************************************************************************
+*** About the DOS utility `hmload' ***
+******************************************************************************
+
+This program was written by John Cobb (Queen Mary, University of London).
+
+John Cobb's note:
+
+ To make use of the ram drive feature I wrote a program `hmload' to load
+ an arbitrary file to an arbitrary address in high memory. The program
+ is not very sophisticated and relies on XMS to turn on the A20 line.
+ (Also one must be very careful to steer clear of any areas of memory
+ already in use).
+
+ Under Linux we generated a disk image `dskimg' (with the kernel and
+ Initrd and a partition table).
+
+ Using this our boot procedure looked something like this:
+
+ hmload -fdskimg -a128
+ fixrb
+ <unload network drivers>
+ grub
+
+ map --ram-drive=0x81
+ map --rd-base=0x8000000
+ map --rd-size=0x400000
+ root (rd,0)
+ kernel /kernel root=/dev/ram0 rw ip=bootp ramdisk_size=32768 ...
+ initrd /initrd
+ boot
+
+See http://sysdocs.stu.qmul.ac.uk/sysdocs/Comment/GrubForDOS/ for details.
+
+Update 2007-12-05:
+
+ Now the MAP command can handle gzipped (rd) image. One can use this
+ feature with the hmload utility. For example,
+
+ step 1. Load the gzipped image under DOS at a relatively low address:
+
+ hmload -fdskimg.gz -a16
+
+ step 2. Unload network drivers.
+
+ step 3. Run GRUB.EXE.
+
+ step 4. At the grub prompt, run these commands:
+
+ map --rd-base=0x1000000 # set rd-base address to be 16M
+ map --rd-size=<the accurate size of dskimg.gz in bytes>
+ map (rd)+1 (hd0) # This will decompress (rd) and place
+ # the decompressed image at the top end
+ # of the extended memory. The (rd)+1
+ # here has special meaning and stands
+ # for the whole (rd) device. You must
+ # use (rd)+1 instead of (rd).
+ map --hook
+ root (hd0,0)
+ kernel /kernel root=/dev/ram0 rw ip=bootp ramdisk_size=32768 ...
+ initrd /initrd
+ map --unhook
+ map (hd0) (hd0) # Delete the map; this is needed.
+ boot
+
+
+******************************************************************************
+*** Notes on the use of stack ***
+******************************************************************************
+
+The protected-mode and real-mode stack are merged at physical address 0x2000.
+
+All functions should use at most 2K stack space(0x1800-0x2000). So each
+subfunction should use as little stack as possible to avoid stack-overflow.
+
+Don't use recursive functions because they could expend too much stack space.
+
+The original protected mode stack at 0x68000(expand-down) is free now and can
+be reused for any purposes.
+
+
+******************************************************************************
+*** A bug was found in the CDROM driver ***
+******************************************************************************
+
+It seems the cdrom must be connected as the master device of an IDE controller.
+
+If cdrom is slave, the driver will fail to read the cdrom sectors. Hope someone
+
+could fix this problem.
+
+
+******************************************************************************
+*** BIOS and the (cd) drive ***
+******************************************************************************
+
+When BIOS boots a no-emulation-mode bootable CD-ROM, it allocates a BIOS drive
+number to the CD. If the boot image of the CD-ROM is grldr or stage2_eltorito,
+then GRUB can access the CD-ROM media through the drive number allocated by
+BIOS. The device name of the CD-ROM is (cd).
+
+BIOS can allocate a BIOS drive number to a no-emulation-mode CDROM even when
+the CDROM is not bootable. QEMU has done so. At boot time, GRUB4DOS will
+search drives 0x80-0xFF for a possible no-emulation-mode CDROM drive allocated
+by BIOS. So if BIOS offered a CDROM interface of int13 EBIOS functions 41h-4Eh,
+then the (cd) device will be automatically available in GRUB4DOS.
+
+
+******************************************************************************
+*** The way of disk emulation changed greatly ***
+******************************************************************************
+
+The way of disk emulation has changed greatly since 0.4.2 final. Please don't
+mix newer versions with older versions when disk emulation features are used.
+
+The newer versions won't automatically unhook emulations established in a
+previous grub4dos environment. The GRUB.EXE of an older version will
+automatically dismiss emulations established earlier, before transferring
+control to the main grub program(i.e., pre_stage2).
+
+
+******************************************************************************
+*** FreeDOS EMM386 v2.26 (2006-08-27) VCPI problem ***
+******************************************************************************
+
+The VCPI function "AX=DE0Ch - Switch From Protected Mode to V86 Mode" of
+FreeDOS EMM386 v2.26 was not implemented properly(it always hangs). As an
+alternative, you can use Microsoft's EMM386 instead.
+
+Even while emm386 is running, grub.exe can be started. But if you try to quit
+to DOS from grub4dos by using the `quit' command, the VCPI function DE0C will
+be called. If EMM386 is of Microsoft, everything goes ok. If EMM386 is of
+FreeDOS, the machine will hang.
+
+
+******************************************************************************
+*** New options for map were added ***
+******************************************************************************
+
+Along with 0.4.2 final, there are two new options for the map command. They
+are --safe-mbr-hook=SMH and --int13-scheme=SCH. Both are related with disk
+emulation for use(as smoothly as possible) in the Win9x environment.
+
+SMH can take either of the two values 0 and 1. By default, SMH is 1. If you
+encountered problems of disk emulation under Win9x, you may insert a line of
+
+ map --safe-mbr-hook=0
+
+before the `boot' command and try again.
+
+Also SCH may take either 0 or 1 at present. By default, SCH is 1. If you
+encountered disk emulation problems under Win9x, you may insert a line of
+
+ map --int13-scheme=0
+
+before the `boot' command and try again.
+
+Note by the way. Like --safe-mbr-hook and --int13-scheme, the MAP command has
+a few other options that are used for setting global variables. They are here:
+
+ map --floppies=M
+
+M can be 0, 1, or 2. MAP will set a proper value at 0040:0010 by using M.
+
+ map --harddrives=N
+
+N can be between 0 and 127(inclusive). MAP will set 0040:0075 to N.
+
+ map --memdisk-raw=RAW
+
+RAW default to 1. If RAW=0, `int15/ah=87h' will be used to access memdrives.
+
+ map --ram-drive=RD
+
+RD default to 0x7F which is a floppy. If the RAM DRIVE is a hard drive image
+(with partition table in the first sector), you should set RD >= 0x80 and RD
+< 0xFF.
+
+ map --rd-base=ADDR
+
+ map --rd-size=SIZE
+
+ADDR specifies the physical base address of the ramdisk image. SIZE specifies
+the size in bytes of the ramdisk image. ADDR default to 0. SIZE is also default
+to 0, but a size of 0 means 4GB, not a zero-long disk. The RAM DRIVE can be
+accessed in the GRUB environment using the (rd) device.
+
+
+******************************************************************************
+*** About the new map option --in-situ ***
+******************************************************************************
+
+--in-situ is used with hard drive images or hardrive partitions. With an
+in-situ map, we can typically use a logical partition as a primary partition.
+
+In-situ map is a whole drive map. It only virtualize the partition table and
+the number of hidden sectors in the BPB of the DOS Boot Record.
+
+While disk emulation may encounter various problems with win9x, the in-situ map
+works fine with win9x.
+
+Note that --in-situ will not change the real partition table.
+
+Example:
+
+ map --in-situ (hd0,4)+1 (hd0)
+
+
+******************************************************************************
+*** The PARTNEW Command Syntax ***
+******************************************************************************
+
+Besides the mappings in the above section, you may instead choose to create a
+new primary partition with the PARTNEW command. PARTNEW can generate a primary
+partition entry (in the partition table) for a logical partition.
+
+For example,
+
+ partnew (hd0,3) 0x07 (hd0,4)+1
+
+where the file (hd0,4)+1 stands for the whole partition (hd0,4). This command
+will create a new primary partition (hd0,3) whose type is 0x07 and whose
+contents/data is the same as that of the logical partition (hd0,4).
+
+Just like a whole logical partition, a contiguous partition image file can
+also be used with PARTNEW:
+
+ partnew (hd0,3) 0x00 (hd0,0)/my_partition.img
+
+The type 0x00 indicates a type-auto-detection of the image MY_PARTITION.IMG.
+The above command will create a new primary partition (hd0,3) with a proper
+type and with contents/data being exactly that of the contiguous file
+(hd0,0)/my_partition.img.
+
+PARTNEW will automatically correct the "hidden sectors" in the BPB and the
+modification will be permanent. And PARTNEW modifies the partition table
+permanently.
+
+In addition to creating new partition entries, PARTNEW can also be used to
+delete(erase, or wipe) a primary partition entry. For example,
+
+ partnew (hd0,3) 0 0 0
+
+which will empty the last entry in the partition table in MBR. Generally,
+you should use the form of "partnew PARTITION 0 0 0" to erase the entry.
+Note that only the entry would be erased, and the data stored in the partition
+will not be touched.
+
+******************************************************************************
+*** Newly implemented operators `&&' and `||' ***
+******************************************************************************
+
+This implementation is very simple. It does not handle operator nesting.
+
+Usage of `&&':
+
+ command1 && command2
+
+Description:
+
+ If command1 returns true, then command2 will be executed.
+
+Usage of `||':
+
+ command1 || command2
+
+Description:
+
+ If command1 returns false, then command2 will be executed.
+
+Examples:
+
+ is64bit && default 0
+ is64bit || default 1
+
+******************************************************************************
+*** Three new commands is64bit, errnum and errorcheck ***
+******************************************************************************
+
+is64bit and errnum retrieve the value of is64bit and errnum respectively.
+
+errorcheck controls whether or not the error will be handled. By default,
+errorcheck is on, and menu script execution will stop on error. If errorcheck
+is off, the script will continue to execute upto a boot command. A boot command
+will turn the errorcheck on.
+
+
+******************************************************************************
+*** Use numeric keys to select a menu entry ***
+******************************************************************************
+
+If, for example, you intend to goto entry #25, you may press 2 followed by 5.
+
+
+******************************************************************************
+*** Use the INSERT key to debug step by step at startup ***
+******************************************************************************
+
+Some buggy machines could fail to enter grub4dos environment. They might hang
+or reboot unexpectedly. Press INSERT as quickly as possible on startup, and
+you can get a chance to single-step the boot process and see how far it can
+go, and then report bugs.
+
+
+******************************************************************************
+*** The debug command syntax has been changed ***
+******************************************************************************
+
+The DEBUG command now can be used to control the verbosity of command output:
+
+ debug [ on | off | normal | status | INTEGER ]
+
+0 or off for silent
+1 or normal for normal
+2 to 0x7FFFFFFF or on for verbose
+
+
+******************************************************************************
+*** GRUB4DOS and Windows Vista ***
+******************************************************************************
+
+First, use the following command to create a boot entry:
+
+ bcdedit /create /d "GRUB for DOS" /application bootsector
+
+The result will look like this:
+
+The entry {05d33150-3fde-11dc-a457-00021cf82fb0} was successfully created.
+
+The long string {05d33150-3fde-11dc-a457-00021cf82fb0} is the id for this
+entry.
+
+Then, use the following commands to set boot parameters:
+
+ bcdedit /set {id} device boot
+ bcdedit /set {id} path \grldr.mbr
+ bcdedit /displayorder {id} /addlast
+
+Please replace {id} with the actual id returned from the previous command.
+
+Finally, copy GRLDR.MBR to C:\ or wherever your boot drive is, and copy GRLDR
+and menu.lst to the root directory of any FAT16/FAT32/EXT2/NTFS partition.
+
+Note: A boot partition should be the active primary partition with BOOTMGR
+ inside. The `device boot' indicates grldr.mbr should be in the boot
+ partition.
+
+Lianjiang has written down a script to automate the tasks:
+
+ @echo off
+ rem by lianjiang
+ cls
+ echo.
+ echo Please run as administrator
+ echo.
+ pause
+ set gname=GRUB for DOS
+ set vid=
+ set timeout=5
+ bcdedit >bcdtemp.txt
+ type bcdtemp.txt | find "\grldr.mbr" >nul && echo. && echo BCD entry existing, no need to install. && pause && goto exit
+ bcdedit /export "Bcd_Backup" >nul
+ bcdedit /create /d "%gname%" /application bootsector >vid.ini
+ for,/f,"tokens=2 delims={",%%i,In (vid.ini) Do (
+ set vida=%%i
+ )
+ for,/f,"tokens=1 delims=}",%%i,In ("%vida%") Do (
+ set vid={%%i}
+ )
+ echo %vid%>vid.ini
+ bcdedit /set %vid% device boot >nul
+ bcdedit /set %vid% path \grldr.mbr >nul
+ bcdedit /displayorder %vid% /addlast >nul
+ bcdedit /timeout %timeout% >nul
+ if exist grldr.mbr copy grldr.mbr %systemdrive%\ /y && goto exit
+ echo.
+ echo Please copy grldr.mbr to %systemdrive%\
+ echo.
+ pause
+ :exit
+ del bcdtemp.txt >nul
+-------------------------------------------------------------------
+Update: Fujianabc pointed out that
+
+ bcdedit /set %vid% device boot >nul
+
+should be changed to
+
+ bcdedit /set %vid% device partition=%SystemDrive% >nul
+-------------------------------------------------------------------
+
+You still need to copy grldr yourself.
+
+Notice: It's possible to modify the BCD entry from a different OS, you just
+need to specify the location of BCD:
+
+ bcdedit /store D:\boot\BCD ...
+
+Notice: These commands need elevated privileges, they should be used inside
+cmd.exe which is started with "Run as administrator".
+
+Notice: People has reported that some version of Vista doesn't support
+creating file in C:\ with no extension, even with administrator privileges.
+This means grldr can't be placed in C:\. You can solve this by either copy
+grldr to another partition, or rename grldr to something like grub.bin. Please
+see the following section on how to do this.
+
+
+******************************************************************************
+*** How to rename grldr ***
+******************************************************************************
+
+grldr and grldr.mbr use internal boot file name to decide which file to load,
+so if you want to change the name, you must also change the embeded setting.
+You can do this with the help of grubinst, which can be downloaded at:
+
+http://download.gna.org/grubutil/
+
+grubinst can generate customized grldr.mbr:
+
+ grubinst -o -b=mygrldr C:\mygrldr.mbr
+
+grubinst can also edit existing grldr/grldr.mbr:
+
+ grubinst -e -b=mygrldr C:\mygrldr
+
+ grubinst -e -b=mygrldr C:\mygrldr.mbr
+
+In this case, you must use a grubinst that is compatible with the version of
+grub4dos, otherwise the edit will fail.
+
+So, in order to load mygrldr instead of grldr, you can use one of the
+following methods:
+
+1. Use customized grldr.mbr to load mygrldr. In this case, you need to change
+the embeded boot file name in grldr.mbr. The name of grldr.mbr can be changed
+at will.
+
+2. Use mygrldr directly. In this case, you need to change the embeded boot
+file name in mygrldr to match its new name.
+
+Notice: The boot file name must conform to the 8.3 naming convention.
+
+
+******************************************************************************
+*** PXE device ***
+******************************************************************************
+
+If PXE service is found at startup, GRUB4DOS will create a virtual device
+(pd), through which files from the tftp server can be accessed. You can setup
+a diskless boot environment using the following steps:
+
+Client side
+
+You need to boot from PXE ROM.
+
+Server side
+
+You need to configure a dhcp server and a tftp server. In the dhcp server, use
+grldr as boot file.
+
+You may also want to load a different menu.lst for different client. GRUB4DOS
+will scan the following location for configuration file:
+
+ [/mybootdir]/menu.lst/01-88-99-AA-BB-CC-DD
+ [/mybootdir]/menu.lst/C000025B
+ [/mybootdir]/menu.lst/C000025
+ [/mybootdir]/menu.lst/C00002
+ [/mybootdir]/menu.lst/C0000
+ [/mybootdir]/menu.lst/C000
+ [/mybootdir]/menu.lst/C00
+ [/mybootdir]/menu.lst/C0
+ [/mybootdir]/menu.lst/C
+ [/mybootdir]/menu.lst/default
+
+Here, we assume the network card mac for the client machine is
+88:99:AA:BB:CC:DD, and the ip address is 192.0.2.91 (C000025B). /mybootdir is
+the directory of the boot file, for example, if boot file is /tftp/grldr, then
+mybootdir=tftp.
+
+If none of the above files is present, grldr will use its embeded menu.lst.
+
+This is a menu.lst to illstrate how to use files from the tftp server.
+
+ title Create ramdisk using map
+ map --mem (pd)/floppy.img (fd0)
+ map --hook
+ rootnoverify (fd0)
+ chainloader (fd0)+1
+
+ title Create ramdisk using memdisk
+ kernel (pd)/memdisk
+ initrd (pd)/floppy.img
+
+You can see that the menu.lst is very similar to normal disk boot, you just
+need to replace device like (hd0,0) with (pd).
+
+There are some differences between disk device and pxe device:
+
+1. You can't list files in the pxe device.
+
+2. The blocklist command will not work with a file in the pxe device.
+
+3. You must use --mem option if you want to map a file in the pxe device.
+
+When you use chainloader to load file from the pxe device, there is a option
+you can use:
+
+ chainloader --raw (pd)/BOOT_FILE
+
+Option --raw works just like --force, but it load file in one go. This can
+improve performance in some situation.
+
+You can use the pxe command to control the pxe device.
+
+1. pxe
+
+ If used without any parameter, pxe command will display current
+ settings.
+
+2. pxe blksize N
+
+ Set the packet size for tftp transmission. Minimum value is 512,
+ maximum value is 1432. This parameter is used primarily for very old
+ tftp server where packet larger than 512 byte is not supported.
+
+3. pxe basedir /dir
+
+ Set the base directory for files in the tftp server. If
+
+ pxe basedir /tftp
+
+ then all files in the pxe device is related to directory /tftp, for
+ example, (pd)/aa.img correspond to /tftp/aa.img in the server.
+
+ The default value of base directory is the directory of the boot file,
+ for example, if boot file is /tftp/grldr, then default base directory
+ is /tftp.
+
+4. pxe keep
+
+ Keep the PXE stack. The default behaviour of GRUB4DOS is to unload
+ the PXE stack just before it exits.
+
+5. pxe unload
+
+ Unload the PXE stack immediately.
+
+
+
+******************************************************************************
+*** New Feature of Relative Path Support ***
+******************************************************************************
+
+Use the `root' or `rootnoverify' command to specify the `working directory'.
+
+For example:
+
+ root (hd0,0)/boot/grub
+
+This specifies that the working dir is (hd0,0)/boot/grub. So all subsequent
+filenames of the form "/..." will actually refer to (hd0,0)/boot/grub/...
+
+That is to say:
+
+ cat /menu.lst
+
+will be equivalent to
+
+ cat (hd0,0)/boot/grub/menu.lst
+
+
+
+******************************************************************************
+*** Notation For The Current Root Device ***
+******************************************************************************
+
+
+The notation `()' can be used to access the current root device. You may use
+`find --set-root ...' to set the current root device, but the find command
+does not set the `working dir' of the root device. In this case you should
+use `()' to set the working dir after the find command:
+
+ root ()/boot/grub
+
+Update 2008-05-01:
+
+ FIND can also set the `working directory' now. For example:
+
+ find --set-root=/tmp /boot/grub/menu.lst
+
+ It is equivalent to this pair of commands:
+
+ find --set-root /boot/grub/menu.lst
+ root ()/tmp
+
+
+******************************************************************************
+*** The new map option --a20-keep-on ***
+******************************************************************************
+
+
+Along with 0.4.3 final, map has a new option --a20-keep-on which is related to
+A20 control after a memdrive sector access. Usage:
+
+ map --a20-keep-on=0
+
+It should be used before the "map --hook" command.
+
+By default, A20 will be always on after an RAM INT13 sector access. If
+"map --a20-keep-on=0" is used, the A20 status after the INT13 call will be the
+same as that before the INT13 call.
+
+
+******************************************************************************
+*** The CDROM emulation (virtualization) ***
+******************************************************************************
+
+The CDROM emulation is sometimes called ISO emulation. Here is an example:
+
+ map (hd0,0)/myiso.iso (hd32)
+ map --hook
+ chainloader (hd32)
+ boot
+
+if myiso.iso is not contiguous and you have enough memory, add a --mem option:
+
+ map --mem (hd0,0)/myiso.iso (hd32)
+ map --hook
+ chainloader (hd32)
+ boot
+
+Note: (hd32) is a grub drive number equivalent to (0xA0). If a virtual drive is
+specified with a drive number greater than or equal to 0xA0, then it will be
+treated as a cdrom (i.e., with 2048-byte big sectors).
+
+Like normal disk emulations, the CDROM emulation also (mainly) works with
+real-mode OSes. After a protected-mode OS kernel (such as
+WinNT/2K/XP/VISTA/LINUX) gains control, the OS would have no ability to access
+the virtual CDROM through BIOS int13.
+
+DOS/Win9x users may google for ELTORITO.SYS and use it in CONFIG.SYS as a
+device driver for the virtual cdrom.
+
+Example usage of eltorito.sys in CONFIG.SYS:
+
+ device=eltorito.sys /D:oemcd001
+
+Corresponding MSCDEX command which can be placed in AUTOEXEC.BAT:
+
+ MSCDEX /D:oemcd001 /L:D
+
+
+Due to some bugs found in eltorito.sys, the driver could fail to load. If you
+encounter such problems, then you may replace (hd32) with (0xFF) for the
+virtual cdrom drive number and try again.
+
+
+******************************************************************************
+*** The New Command CHECKRANGE ***
+******************************************************************************
+
+Checkrange checks whether or not the return value of a command is in the
+specified range or ranges.
+
+Usage: checkrange RANGE COMMAND
+
+Here are some examples for RANGE:
+
+ 3 is a range containing only the number 3
+ 3:3 is equivalent to 3
+ 3:8 is a range containing the numbers 3, 4, 5, 6, 7, 8
+ 3,4,5,6,7,8 is equivalent to 3:8
+ 3:5,6:8 is also equivalent to 3:8
+ 3,4:7,8 is also equivalent to 3:8
+
+Note: You should not insert spaces into a range.
+
+Here is an example showing where the checkrange can be used:
+
+ checkrange 0x05,0x0F,0x85 parttype (hd0,1) || hide (hd0,1)
+
+which means: if (hd0,1) is not an extended partition, then hide it.
+
+
+******************************************************************************
+*** The New Command TPM ***
+******************************************************************************
+
+The "tpm --init" uses 512-byte data at 0000:7C00 as buffer to initialise TPM.
+
+Before you boot VISTA's BOOTMGR, you might have to use the "tpm --init"
+command on some machines. Normally you want to issue the "tpm --init" command
+after a CHAINLOADER command.
+
+
+******************************************************************************
+*** Delimitors or comments between titles ***
+******************************************************************************
+
+It is possible to use titles as delimitors or comments. A title(or menu item)
+is called unbootable if all of its menu commands are not boot-sensitive.
+
+The following commands are boot-sensitive(and others are not boot-sensitive):
+
+ boot
+ bootp
+ chainloader
+ configfile
+ embed
+ commandline
+ halt
+ install
+ kernel
+ pxe
+ quit
+ reboot
+ setup
+
+An unbootable title will be skipped when the user presses the Up Arrow or Down
+Arrow keys. Even the unbootable menu item can get accessed(and executed) by
+using the Left Arrow and/or Right Arrow keys. Examples:
+
+ title This is an UNBOOTABLE entry(so this line is also a comment)
+ pause --wait=0 This title is a comment. Nothing to do.
+ pause --wait=0 You can use non-boot-sensitive commands here
+ pause --wait=0 of any kind and as many as you would like.
+ help
+ help root
+ help chainloader
+ help parttype
+ clear
+ title ------------------------------------------------------------
+ pause --wait=0 This title is a delimitor. Nothing to do.
+ pause --wait=0 You can use non-boot-sensitive commands here
+ pause --wait=0 of any kind and as many as you would like.
+ clear
+ help
+ help boot
+ title ============================================================
+ pause --wait=0 This title is a delimitor. Nothing to do.
+ pause --wait=0 You can use non-boot-sensitive commands here
+ pause --wait=0 of any kind and as many as you would like.
+ help
+ clear
+ help pause
+ title ************************************************************
+ pause --wait=0 This title is a delimitor. Nothing to do.
+ pause --wait=0 You can use non-boot-sensitive commands here
+ pause --wait=0 of any kind and as many as you would like.
+ help kernel
+ help
+ clear
+
+Note: An unbootable menu item must contain at least one command. If there
+are no commands for a title, the title will be simply discarded and disappear.
+
+
+******************************************************************************
+*** Bifurcate drives ***
+******************************************************************************
+
+Some machines apply different actions to a drive between CHS and LBA mode.
+When you read sectors using standard BIOS call int13/AH=02h, you might find
+out the drive is a floppy. But when you read sectors using extended BIOS
+call(EBIOS) int13/AH=42h, you could know the drive is a cdrom. Such a drive
+is called bifurcate.
+
+A bifurcate drive can have two drive numbers: one is the normal BIOS drive
+number between 00 and FF in hexa, and this drive uses only CHS mode disk
+access(standard BIOS int13/AH=02h); the other is the normal BIOS drive number
+(Bitwise) OR'ed by 0x100(i.e., 256 in decimal), and this drive uses only
+LBA mode disk access(EBIOS int13/AH=42h). For example, if the drive 0x00
+(i.e., the first floppy) is bifurcate, then the drive (0x00) uses CHS mode
+to access its sectors, and the drive (0x100) uses LBA (meaning EBIOS) mode
+to access its sectors.
+
+The geometry command can report the disk access mode for bifurcate drives as
+BIF instead of the conventional CHS or LBA.
+
+Known bifurcate drives. Virtual PC and some real machines are found to create
+a bifurcate floppy drive when they boot from a floppy-emulation mode bootable
+cdrom. The "geometry (fd0)" will show
+
+ drive 0x00(BIF): C/H/S=...Sector Count/Size=.../512
+
+and "geometry (0x100)" will show
+
+ drive 0x100(BIF): C/H/S=...Sector Count/Size=.../2048
+
+Actually (0x100) can access the whole cdrom, you may "ls (0x100)/" and find
+your files on the cdrom(not the files inside the booted floppy image). Of
+course "ls (fd0)/" will list the files inside the booted floppy image.
+
+Note that only some (real or virtual) machines have this action, others
+will not produce bifurcate drives.
+
+
+******************************************************************************
+*** GRLDR as PXE boot file ***
+******************************************************************************
+
+GRLDR can be used as the PXE boot file on a remote/network server. The (pd)
+device is used to access files on the server. When GRLDR is booted through
+network, it will use its preset menu as the config file. However, you may use
+a "pxe detect" command, which acts the same way as PXELINUX:
+
+ * First, it will search for the config file using the hardware type (using
+ its ARP type code) and address, all in hexadecimal with dash separators;
+ for example, for an Ethernet (ARP type 1) with address 88:99:AA:BB:CC:DD
+ it would search for the filename 01-88-99-AA-BB-CC-DD.
+
+ * Next, it will search for the config file using its own IP address in
+ upper case hexadecimal, e.g. 192.0.2.91 -> C000025B. If that file is not
+ found, it will remove one hex digit and try again. At last, it will try
+ looking for a file named default (in lower case). As an example, if the
+ boot file name is /mybootdir/grldr, the Ethernet MAC address is
+ 88:99:AA:BB:CC:DD and the IP address 192.0.2.91, it will try following
+ files (in that order):
+
+ /mybootdir/menu.lst/01-88-99-AA-BB-CC-DD
+ /mybootdir/menu.lst/C000025B
+ /mybootdir/menu.lst/C000025
+ /mybootdir/menu.lst/C00002
+ /mybootdir/menu.lst/C0000
+ /mybootdir/menu.lst/C000
+ /mybootdir/menu.lst/C00
+ /mybootdir/menu.lst/C0
+ /mybootdir/menu.lst/C
+ /mybootdir/menu.lst/default
+
+You cannot directly map an image file on (pd). You must map it in memory using
+the --mem option. For example,
+
+ map --mem (pd)/images/floppy.img (fd0)
+ map --hook
+ chainloader (fd0)+1
+ rootnoverify (fd0)
+ boot
+
+One more example,
+
+ map --mem (pd)/images/cdimage.iso (0xff)
+ map --hook
+ chainloader (0xff)
+ boot
+
+
+******************************************************************************
+*** New program badgrub.exe ***
+******************************************************************************
+
+The new program badgrub.exe is intended to serve 'bad' machines(typically some
+DELL models) that cannot run the normal grub.exe.
+
+
+******************************************************************************
+*** Conditional find ***
+******************************************************************************
+
+The new find syntax allows to find a device conditionally.
+
+ find [OPTIONS] [FILENAME] [CONDITION]
+
+CONDITION is a normal grub command which returns TRUE or FALSE.
+
+ Example 1:
+
+ find
+
+ This will list all partitions, all floppies and the (cd).
+
+ Example 2:
+
+ find +1
+
+ This will list all devices with a known filesystem.
+
+ Example 3:
+
+ find checkrange 0xAF parttype
+
+ This will list all partitions with ID=0xAF.
+
+ Example 4:
+
+ find /ntldr checkrange 0x07 parttype
+
+ This will list all partitions with ID=0x07 and existing /ntldr.
+
+
+
+******************************************************************************
+*** How to build grldr boot images ***
+******************************************************************************
+
+1. build 1.44M floppy image ext2grldr.img
+
+ dd if=/dev/zero of=ext2grldr.img bs=512 count=2880
+ mke2fs ext2grldr.img
+ mkdir ext2tmp
+ mount -o loop ext2grldr.img ext2tmp
+ cp default ext2tmp
+ cp menu.lst ext2tmp
+ cp grldr ext2tmp
+ umount ext2tmp
+ bootlace.com --floppy --chs --sectors-per-track=18 --heads=2 --start-sector=0 --total-sectors=2880 ext2grldr.img
+
+2. build 1.44M floppy image fat12grldr.img
+
+ dd if=/dev/zero of=fat12grldr.img bs=512 count=2880
+ mkdosfs fat12grldr.img
+ mkdir fat12tmp
+ mount -o loop fat12grldr.img fat12tmp
+ cp default fat12tmp
+ cp menu.lst fat12tmp
+ cp grldr fat12tmp
+ umount fat12tmp
+ bootlace.com --floppy --chs fat12grldr.img
+
+3. build iso9660 CDROM image grldr.iso
+
+ mkdir iso_root
+ cp grldr iso_root
+ cp menu.lst iso_root
+ mkisofs -R -b grldr -no-emul-boot -boot-load-size 4 -o grldr.iso iso_root
+
+
+******************************************************************************
+*** Use bootlace.com to install partition boot record ***
+******************************************************************************
+
+Since bootlace.com has not implemented the --install-partition option, you
+need to use the already implemented --floppy=PartitionNumber option instead.
+
+Hear is a way you might want to follow:
+
+Step 1. Get the boot sectors of the partition and save to a file MYPART.TMP.
+ For NTFS, you need to get the beginning 16 sectors. For other type of
+ filesystems, you only need to get one sector, but getting more sectors
+ is also ok.
+
+Step 2. Run this:
+
+ bootlace.com --floppy=Y --sectors-per-track=S --heads=H --start-sector=B --total-sectors=C --vfat --ext2 --ntfs MYPART.TMP
+
+ where we suppose MYPART.TMP is for (hdX,Y) and the partition number Y
+ should be specified as in the --floppy=Y option.
+
+ Note that for FAT12/16/32/NTFS partitions, you can omit these options:
+
+ --sectors-per-track, --heads, --start-sector, --total-sectors,
+ --vfat and --ext2.
+
+ For NTFS partitions, you must specify --ntfs option.
+
+ For ext2 partitions, you can omit --vfat, --ntfs and --ext2 options,
+ but other options should be specified.
+
+Step 3. Put MYPART.TMP back on to the boot sector(s) of your original partition
+ (hdX,Y).
+
+
+Note: Only a few file systems(FAT12/16/32/NTFS/ext2/ext3) are supported by now.
+
+Note2: Under Linux you may directly write the partition. That is to say, Step
+ 1 and Step 3 are not needed. Simply use its device name instead of
+ MYPART.TMP.
+
+Note3: grubinst has the feature of installing grldr boot code onto a
+ partition boot area.
+
+******************************************************************************
+*** Use a single key to select menu item ***
+******************************************************************************
+
+Some machines have a simplified keyboard. The keyborad might have only the
+number keys 0 .. 9 plus a few other keys. When the menu displayed, the user
+can strike a key for 8 times. When the menu handler detects the continuous
+single keypress, it will assume the user want to use this key to select a menu
+item and boot. This single key will act as the RIGHT-ARROW key for the user to
+select a menu item. And 5 seconds later after the user stops the keypress,
+the selected menu item will automatically boot. Any normal keys can be used as
+a single key for this purpose, except for a few functional keys like b, e,
+Enter, etc. Once another key is pressed, the feature of Single-Key-Selection
+will disappear immediately.
+
+
+******************************************************************************
+*** Parameter file for bootlace running under DOS ***
+******************************************************************************
+
+You may move all or part of the command-line arguments into a file. The file
+can have multi lines. Just like SPACEs and TABs, the CRs and LFs can also
+delimit the commandline arguments in the parameter file.
+
+Example:
+
+ bootlace < my_parafile
+ bootlace --read-only my_mbr < my_other_options
+
+Note: Pipes do not work. You have to use the input-redirection operator(<).
+
+
+******************************************************************************
+*** Use bootlace to create a triple MBR ***
+******************************************************************************
+
+This is typically used for USB drives, though it also works with hard drives.
+
+Steps to create triple MBR:
+
+1. Do a fresh FDISK to create a FAT12/16/32 partition starting at sector 95
+(in LBA, that is, the begginning sector(MBR) is sector 0).
+
+2. Install grldr boot sector onto the boot sector of this partition. See
+section "Use bootlace.com to install partition boot record" above.
+
+3. Get 96 sectors of the drive starting at sector 0(MBR), and save to file
+MYMBR96.TMP.
+
+4. Run bootlace.com:
+
+ bootlace.com MYMBR96.TMP
+
+5. Put MYMBR96.TMP back onto the drive starting at MBR(sector 0).
+
+Note: If the drive already has a triple MBR, then bootlace will cancel it
+and restore the original partition layout.
+
+
+******************************************************************************
+*** Use 'pxe detect' in preset-menu ***
+******************************************************************************
+
+Now the "pxe" command has a new subcommand "detect":
+
+ pxe detect [BLOCK_SIZE] [MENU_FILE]
+
+BLOCK_SIZE specifies the block size for PXE. If it is not specified or it is
+0, then grub4dos will go through a probing process and get a proper value
+for data transfer.
+
+MENU_FILE specifies the config file on the PXE server. If omitted, a standard
+config file in the menu.lst sub-dir will gain control. For a description on
+the config files in the menu.lst sub-dir, please refer to the section
+"GRLDR as PXE boot file" above.
+If MENU_FILE starts in a "/", then the MENU_FILE on the PXE server will gain
+control, else(if MENU_FILE does not start in a "/") no menu will be executed.
+
+Normally you want to use a "pxe blksize ..." or a "pxe detect ..." command
+before you access the (pd) device, since the default blocksize of 512 might
+not work on your system.
+
+
+******************************************************************************
+*** Use 'configfile' in preset-menu ***
+******************************************************************************
+
+Now the preset menu holds the highest priority. It will gain control prior to
+the menu.lst on the boot device. If a 'configfile' command(without specifying
+any file as the parameter) occurs in the menu init command group of the preset
+menu, then control will go to the menu.lst on the boot device.
+
+Note: You should better not use "configfile ANOTHER_MENU" frequently in your
+menu.lst file, because it could create infinite loop and thus hang your
+computer.
+
+
+******************************************************************************
+*** New command 'dd' to copy files ***
+******************************************************************************
+
+Usage:
+
+dd if=IF of=OF [bs=BS] [count=C] [skip=IN] [seek=OUT] [buf=ADDR] [buflen=SIZE]
+
+Copy file IF to OF. BS is blocksize in bytes, default to 512. C is blocks to
+copy, default is total blocks in IF. IN specifies number of blocks to skip
+when read, default is 0. OUT specifies number of blocks to skip when write,
+default is 0. Skipped blocks are not touched. Both IF and OF must exist.
+
+Both IF and OF must have a leading device name, i.e., of the form `(...)'.
+You may use `()' for the current root device.
+
+dd can neither enlarge nor reduce the size of OF, the leftover tail of IF
+will be discarded. OF cannot be a gzipped file. If IF is a gzipped file,
+it will be decompressed automatically when copying.
+
+dd is dangerous, use at your own risk. To be on the safe side, you should
+only use dd to write a file in memory.
+
+In some cases when writing a file in a NTFS volume, dd might fail.
+
+If you attempt to write a device or a block file that is not in memory by
+starting dd in a menu, you will safely be refused :-) (Update: no restrictions
+now)
+
+Update: New options are implemented for user defined buffer. By default,
+the buffer is at address 0x50000, and length is 0x10000(=64KB). You cannot
+specify ADDR to be lower than 0x100000(=1MB). Besides, you must specify SIZE
+larger than 0x10000(=64KB). Normally you want ADDR >= 0x1000000(=16MB), and
+SIZE also >= 16MB. A large SIZE could speed up the progression of dd.
+
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+!!!!~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!!!!
+!!!! Caution! Both IF and OF can be a device name which stands for !!!!
+!!!! all the sectors on the device. Take utmost care! !!!!
+!!!!______________________________________________________________________!!!!
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+
+******************************************************************************
+*** New command 'uuid' to identify partitions ***
+******************************************************************************
+
+Usage:
+
+ uuid [DEVICE] [UUID]
+
+If DEVICE is not specified, search for filesystem with UUID in all partitions
+and set the partition containing the filesystem as new root (if UUID is
+specified), or just list uuid's of all filesystems on all devices (if UUID is
+not specified). If DEVICE is specified, return true or false according to
+whether or not the DEVICE matches the specified UUID (if UUID is specified),
+or just list the uuid of DEVICE (if UUID is not specified).
+
+Example 1:
+
+ find --set-root uuid () 7f95820f-5e33-4e6c-8f50-0760bf06d79c
+
+which will find a partition with uuid=7f95820f-5e33-4e6c-8f50-0760bf06d79c
+and set the partition as root if found.
+
+Example 2:
+
+ uuid ()
+
+which will print the uuid of the current root device.
+
+
+******************************************************************************
+*** gfxmenu support in grub4dos ***
+******************************************************************************
+
+Gfxmenu support has been added to grub4dos. To use it, you must first find the
+message file you need, then load it in menu.lst with command like this:
+
+ gfxmenu /message
+
+This should be a gloabl command, that is, not inside any menu item. Also, it
+can only be used in configure file, running it in console mode does not work.
+
+gfxmenu does not work in conjunction with the password feature.
+
+There are two major format of message file. Old format is created with gfxboot
+3.2.* or older (size of message file is normally about 150K), while new format
+is created with gfxboot 3.3.* and later (size of message file is normally above
+300K). Both format are supported in grub4dos.
+
+
+******************************************************************************
+*** Use 'write' to write a string into a device or file ***
+******************************************************************************
+
+Usage:
+
+ write [--offset=SKIP] ADDR_OR_FILE INTEGER_OR_STRING
+
+SKIP is an integer and defaults to 0.
+
+If ADDR_OR_FILE is an integer, then it is treated as a memory address, and
+INTEGER_OR_STRING must be an integer value. The integer INTEGER_OR_STRING
+will be written to address (ADDR_OR_FILE + SKIP).
+
+If ADDR_OR_FILE is a device or a file, then INTEGER_OR_STRING is treated as
+a string which will be written to ADDR_OR_FILE at offset SKIP (in bytes).
+
+The string is quoted with nothing, that is, neither with the single quote
+char(') nor with the double quote char(").
+
+Space char must be quoted with back slash(\). (Update: need not now)
+
+Single quote char(') and double quote char(") are not interpreted specially
+and can be used directly in the string.
+
+Some C-style quote sequences are interpreted as follows:
+
+ \NNN character with octal value NNN (1 to 3 digits)
+
+ \\ backslash
+
+ \a alert (BEL)
+
+ \b backspace
+
+ \f form feed
+
+ \n new line
+
+ \r carriage return
+
+ \t horizontal tab
+
+ \v vertical tab
+
+ \xHH byte with hexadecimal value HH (1 to 2 digits)
+
+Just like dd, the write can neither enlarge nor reduce the size of the
+destination file, the leftover tail of the string will be discarded.
+The destination file cannot be a gzipped file.
+
+Again like dd, the write command is also dangerous, use at your own risk.
+And to be on the safe side, you should only write to memory files.
+
+In some cases when writing a file in a NTFS volume, the write might fail.
+
+If you attempt to write a device or a block file that is not in memory by
+using write in a menu, you will safely be refused :-) (Update: no restrictions
+now)
+
+
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+!!!!~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~!!!!
+!!!! Caution! The file to write can be a device name which stands !!!!
+!!!! for all the sectors on the device. Take utmost care! !!!!
+!!!!______________________________________________________________________!!!!
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+
+******************************************************************************
+*** Item-by-item help text for menu entries ***
+******************************************************************************
+
+
+The help message at the bottom of the screen will vary as you choose the menu.
+
+You may append your help text to the title line. The help text must begin
+with "\n", for example:
+
+ title This is the title\nThis is the help text.\nAnd this is the 2nd line of the help text.
+
+Some C-style quote sequences are interpreted as stated in the section above.
+
+
+******************************************************************************
+*** initrd can load multiple cpio files for Linux 2.6 kernels ***
+******************************************************************************
+
+Usage:
+
+ initrd FILE [FILE ...]
+
+Note 1: You should not load more than one oldstyle disk images in this way,
+because this is not supported by Linux kernel.
+
+Note 2: The FILEs should be specified in the same order as with syslinux.
+
+******************************************************************************
+*** access some internel variables at a fixed location ***
+******************************************************************************
+
+Address Length Description
+========= ======== ==============================================
+0000:8208 4 (DWORD) install_partition (the boot partition)
+0000:8280 4 (DWORD) boot_drive (the boot drive)
+0000:8284 4 (DWORD) pxe_yip (your ip)
+0000:8288 4 (DWORD) pxe_sip (server ip)
+0000:828C 4 (DWORD) pxe_gip (gateway ip)
+0000:8290 8 (QWORD) filesize (file size by last "cat --length=0")
+0000:8298 4 (DWORD) saved_mem_upper (extended memory size in KB)
+0000:829C 4 (DWORD) saved_partition (current root partition)
+0000:82A0 4 (DWORD) saved_drive (current root drive)
+0000:82A4 4 (DWORD) no_decompression (no auto gunzip)
+
+Note 1: Filesize can be initialised/modified by using "cat --length=0 FILE".
+Note 2: You should not write these variables by hand(should read only).
+Note 3: You may use 1K at 6000:0000 for your own varibles(See note 4).
+Note 4: The read command now returns the integer value at the given address.
+Note 5: Grub4dos does not have the variable expansion feature. You can only
+ use integer variables. You need not declare them, but use the memory
+ address directly. Usually you want to use variables as a logical
+ value or in a command for conditional test, e.g., of this form:
+ "checkrange RANGE read ADDR"
+Note 6: no_decompression, saved_drive and saved_partition are writable.
+
+
+******************************************************************************
+*** possibility to run another menu.lst after gfxmenu ***
+******************************************************************************
+
+Notice the use of CONFIGFILE after GFXMENU in the following example:
+
+ # The menu.lst file for gfxmenu
+ default=0
+ timeout=5
+ gfxmenu /message
+ configfile /another.lst
+ title 0..........
+ ................
+ title 1..........
+ ................
+ title 2..........
+ ................
+ # End of menu.lst
+
+ # Begin another.lst
+ default=0
+ timeout=5
+ title 0..........
+ ................
+ title 1..........
+ ................
+ title 2..........
+ ................
+ # End of another.lst
+
+This will try gfxmenu command first. On exit(or on failure) control will go
+to another.lst file.
+
+
+******************************************************************************
+*** a range of drives can be unmapped ***
+******************************************************************************
+
+Usage:
+
+ map --unmap=RANGE
+
+RANGE is a range of BIOS drive numbers to be unmapped. BIOS drive number 0
+is for the first floppy, 1 is for the second floppy; 0x80 is for the first
+hard drive, 0x81 is for the second hard drive, etc; virtual cdrom (hd32)
+corresponds to BIOS drive number 0xA0, (hd33) corresponds to 0xA1, etc.
+
+For description on RANGE, please refer to section `The New Command CHECKRANGE'
+above.
+
+Example 1:
+
+ map --unmap=0,0x80,0xff
+
+This will unmap virtual floppy (fd0), virtual hard drive (hd0) and virtual
+cdrom (0xff).
+
+Example 2:
+
+ map --unmap=0:0xff
+
+This will unmap all virtual floppies, all virtual hard drives and all virtual
+cdroms.
+
+Note 1: Normally a `map' command will add an item in the drive map table for
+ a virtual drive. But `--unmap' means items in the drive map table
+ (for the specified virtual drives) will be deleted.
+Note 2: The --unhook option only breaks the INT13 hook(to the inerrupt
+ vector table). It will not affect the drive map table. And later on
+ execution of a `boot' command, the INT13 disk emulation routine will
+ automatically get hooked(to the interrupt vector table) when needed
+ (e.g., the drive map table is non-empty) even if it has been unhooked.
+Note 3: Usually you want to do a `map --rehook' after you have changed the
+ drive map table.
+
+
+******************************************************************************
+*** geometry tune and sync ***
+******************************************************************************
+
+When a USB storage device is connected to a (or another) machine, the geometry
+in the partition table or in the BPB of the volume could be invalid, and the
+machine could hang at boot time. So you need to find out the correct geometry
+for the drive (use `geometry --tune'), and then update the geometry in
+partition table and BPB of the drive(use `geometry --sync').
+
+The above steps are required if you are going to boot DOS, because DOS
+requires the right geometry in the partition table and BPB. Windows/Linux may
+also require it, since the boot process could run in real-mode.
+
+
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