Windows XP in-depth analysis of BOOT.INI

A friend who has multiple operating systems installed on the computer knows that after the computer is powered on, a boot menu will appear, which lists all the operating systems installed on this computer. The user uses “↑ ”“↓” keys can choose which system to enter. In fact, all of this stems from a file called BOOT.INI, which has existed on Windows systems since Windows NT. Windows XP relies primarily on the BOOT.INI file to determine which operating system categories are available for display during the reboot (boot) process. In general, it is located in the root directory of the C drive. By default, it is a hidden read-only system configuration file. To view it, just remove its hidden properties, you can open it with Notepad, or you can run msconfig.exe in “Start”, click “BOOT in the pop-up "System Configuration Utility" dialog box. The .INI” tab will give you a glimpse of the true colors of the mountains. Let's take a look at the BOOT.INI file in the author's computer (see Figure 1).
Figure 1 Startup menu before modification

The common format of the BOOT.INI file is as follows:

[boot loader]

timeout=30

default=multi(0)disk(0)rdisk(0)partition(1)\\WINDOWS

[operating systems]

multi(X)disk(Y)rdisk(Z) Partition(Q)\\WINDOWS="Microsoft Windows XP Professional" /fastdetect

SCSI(X)disk(Y)rdisk(Z)partition(Q)\\WIN98="Microsoft Windows 98" /fastdetect< Br>

This file is divided into two parts: Boot loader and Operating systems. In the bootloading section, timeout=xx indicates the time to wait for the user to select the operating system. The default is 30 seconds, and the user can change it as needed. Default=xxxx indicates the default operating system path to be loaded by default, which is represented by the highlight bar part waiting for user selection at startup. But what puzzles many users is, what do you mean by "multi(0)disk(0)rdisk(0)partition(1)”?

Actually this is named according to the ARC rules, which is a common method for identifying devices in x86 or RISC computers. The ARC name points to the partition where the operating system files are stored. For disk devices, the ARC name is composed as follows:

(X)disk(Y)rdisk(Z)partition(Q)

Two valid values, multi and SCSI, are used to identify the hardware adapter. Multi indicates a non-SCSI hard disk or a SCSI hard disk accessed by the SCSI BIOS, while SCSI indicates a SCSI hard disk that is prohibited by the SCSI BIOS. The X value indicates the serial number of the disk controller where the hard disk where the operating system's system root directory is located is located on the same disk controller (X starts from 0).

disk(Y): For SCSI hard disks, the Y value indicates the hard disk serial number of the hard disk on the same disk controller where the operating system's system root directory is located (Y starts from 0); For multi, the Y value has no meaning and is always 0.

rdisk(Z): For multi, the Z value indicates the hard disk serial number of the hard disk on the same disk controller where the operating system's system root directory is located (Z starts from 0); for SCSI For the hard disk, the Z value is meaningless and is always 0.

partition(Q): The Q value indicates the serial number of the primary partition of the operating system's system root directory on the same hard disk (Q starts from 1).

The Operating Systems section lists the paths and listings for all operating systems on this computer, including some such as /fastdetect, /basevideo, /sos. These switches have special meanings and are generally not recommended for changes.

OK, based on the above knowledge, we should have a clear understanding of the BOOT.INI file. So we can modify it as needed. Take the author's computer as an example. The BOOT.INI file shows that there are two Windows XP Professional systems installed in the hard disk (actually one for the Chinese version and one for the English version). By default, the system on the third partition of the hard disk is started. (English version). If you want it to start the system on the first partition of the hard disk by default (Chinese version), and in order to distinguish, mark the corresponding two Windows XP Professional. At this time, we can achieve the purpose by modifying the BOOT.INI file, as shown in Figure 2. Restart your computer and see if your wishes are fulfilled!

Figure 2 Startup menu after modification

From the above, BOOT.INI is a very important system file. Without it, the system will not be able to boot, so we In addition to making the necessary backups, you have to edit its methods. Especially when installing multiple systems, if you do not follow the installation order from low to high (Windows 98, Windows 2000, Windows XP, Windows 2003), the file will often be damaged. If we master the way to modify and edit it, we won't have time to do it.