Grub For Dos

Project Name: GRUB for DOS Definition: A GRUB build for DOS with extensions for disk drive emulation. Current Version: 0.4.1 Author: Tinybit(tinybit@tom.com) File Format: DOS EXE executable Purpose: Launch GRUB boot loader from within DOS Circumstanced Use: in CONFIG.SYS or AUTOEXEC.BAT Ability: Boot any installed operating system on your PC Limitations: GRUB.EXE only runs in real mode DOS. It cannot run from a DOS BOX inside Windows. Besides, GRUB cannot run if EMM386.EXE in CONFIG.SYS line is loaded. Similarly it does not run if some TSR programs is running. Currently runs on MS-DOS 3.30, 4.0, 5.0, 6.0, 6.20. 6.21, 6.22, 7.0(Win95), 7.10(Win98), 8.0(WinME/NT/2000/XP), and FreeDOS(build 2029 and hopefully more future builds). Currently could not return to DOS after GRUB.EXE was started. Copyright(C): Tinybit(tinybit@tom.com) License: GNU GPL(see file COPYING) source available as diff patches to the GNU GRUB release. See the shell script COMPILE for more info. WARRANTY: NO WARRANTY(see file COPYING) TO DO: Build for running on other DOS versions. Usage: GRUB [ --config-file=FILE ] The FILE, for example, can be (hd0,0)/boot/grub/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)/boot/grub/menu.lst as the configure file, if it exists. The partition (hd0,0) can be a Windows partition or a Linux partition, or any other partition type supported by GRUB. 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. -------------------------------------------------------- FTP site: (temporarily) ftp://ftp.linuxeden.com/tinybit/ Web site: http://sarovar.org/projects/grub4dos/ Web site: http://grub4dos.jot.com/ Web site: http://grub4dos.freespaces.com/ Web site: http://newdos.yginfo.net/grubdos.htm (Thanks to Wengier) Web site: http://grub4dos.sourceforge.net/ (WinGRUB by bean123) Web site: http://grub.linuxeden.com/ (scratchpad, mainly in Chinese) 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. Even if the drive letter of this disk has been changed to other than C by Windows device manager, it seems you still have to use the letter C here in BOOT.INI, otherwise, NTLDR might fail to locate the GRLDR file. Besides, the filename GRLDR in the root directory must be unchanged. If the partition type is NTFS, you should also place the same copy of GRLDR and menu.lst in the root directory of an FAT12/16/32 partition according to the following NOTICE. Notice! In the future, we will remove NTFS support. For Windows users, please create an FAT partition and place GRLDR and menu.lst there. From now on, please don't report bugs relevant to NTFS. Someone reports that Windows XP with newer SPs and Windows Vista have intentionally broken the compatiblity with many things(including GRLDR). So you will get into trouble with these systems. 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 a 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 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 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 0xff, because 0xff is for the (md) device). Update 9: Directly boot NTLDR of WinNT/2K/XP and IO.SYS of Win9x/ME and