See also
- GNU GRUB
- LILO (bootloader)
- GAG (Gestor de Arranque Gráfico)
- SYSLINUX
- WinKExec
- Win32-loader (Debian)
| Developer(s) | Hans Lermen, Samuel Thibault |
|---|---|
| Stable release | 1.6f / September 17, 2012 |
| Operating system | DOS |
| Type | Bootloader |
| License | GPL-2.0-or-later |
| Website | Official website |
loadlin is a Linux boot loader that runs under 16-bit real-mode DOS (including the MS-DOS mode of Windows 95, Windows 98 and Windows Me startup disk). It allows the Linux system to load and replace the running DOS without altering existing DOS system files.
loadlin and the Linux kernel are both files on a file system accessible to DOS. It loads the Linux kernel into memory from a file. It also places various configuration parameters into memory, and transfers control to the kernel. The kernel reads these parameters, initializes and runs, replacing DOS completely.
Optionally, it can be configured to supply the kernel with an initial RAM disk, loaded into memory before transferring control to the Linux kernel. It passes to the kernel information about the RAM disk and its location. Furthermore, parameters can be passed to the Linux kernel that make it use that RAM disk as its root file system. The startup programs in that file system often cause Linux to mount another file system (perhaps on a fixed disk) and switch to using that as its root file system.
loadlin operates as a separate program and does not modify the master boot record, which can be useful for situations where there are concerns about modifying the MBR (which could lead to an unbootable system if done incorrectly). Due to its structure, loadlin only works on DOS-based operating systems, and will not work on NT-based versions of Windows.
In computing, booting is the process of starting a computer as initiated via hardware such as a button or by a software command. After it is switched on, a computer's central processing unit (CPU) has no software in its main memory, so some process must load software into memory before it can be executed. This may be done by hardware or firmware in the CPU, or by a separate processor in the computer system.
GNU GRUB is a boot loader package from the GNU Project. GRUB is the reference implementation of the Free Software Foundation's Multiboot Specification, which provides a user the choice to boot one of multiple operating systems installed on a computer or select a specific kernel configuration available on a particular operating system's partitions.
NTLDR is the boot loader for all releases of Windows NT operating system from 1993 with the release of Windows NT 3.1 up until Windows XP and Windows Server 2003. From Windows Vista onwards it was replaced by the BOOTMGR bootloader. NTLDR is typically run from the primary storage device, but it can also run from portable storage devices such as a CD-ROM, USB flash drive, or floppy disk. NTLDR can also load a non NT-based operating system given the appropriate boot sector in a file.
A boot disk is a removable digital data storage medium from which a computer can load and run (boot) an operating system or utility program. The computer must have a built-in program which will load and execute a program from a boot disk meeting certain standards.
In computer operating systems, memory paging is a memory management scheme by which a computer stores and retrieves data from secondary storage for use in main memory. In this scheme, the operating system retrieves data from secondary storage in same-size blocks called pages. Paging is an important part of virtual memory implementations in modern operating systems, using secondary storage to let programs exceed the size of available physical memory.
A live CD is a complete bootable computer installation including operating system which runs directly from a CD-ROM or similar storage device into a computer's memory, rather than loading from a hard disk drive. A live CD allows users to run an operating system for any purpose without installing it or making any changes to the computer's configuration. Live CDs can run on a computer without secondary storage, such as a hard disk drive, or with a corrupted hard disk drive or file system, allowing data recovery.
A bootloader, also spelled as boot loader or called boot manager and bootstrap loader, is a computer program that is responsible for booting a computer.
UEFI is a set of specifications written by the UEFI Forum. They define the architecture of the platform firmware used for booting and its interface for interaction with the operating system. Examples of firmware that implement these specifications are AMI Aptio, Phoenix SecureCore, TianoCore EDK II and InsydeH2O.
Linux Terminal Server Project (LTSP) is a free and open source terminal server for Linux that allows many people to simultaneously use the same computer. Applications run on the server with a terminal known as a thin client handling input and output. Generally, terminals are low-powered, lack a hard disk and are quieter and more reliable than desktop computers because they do not have any moving parts.
BIOS interrupt calls are a facility that operating systems and application programs use to invoke the facilities of the Basic Input/Output System firmware on IBM PC compatible computers. Traditionally, BIOS calls are mainly used by DOS programs and some other software such as boot loaders. BIOS runs in the real address mode of the x86 CPU, so programs that call BIOS either must also run in real mode or must switch from protected mode to real mode before calling BIOS and then switching back again. For this reason, modern operating systems that use the CPU in Protected mode or Long mode generally do not use the BIOS interrupt calls to support system functions, although they use the BIOS interrupt calls to probe and initialize hardware during booting. Real mode has the 1MB memory limitation, modern boot loaders use the unreal mode or protected mode to access up to 4GB memory.
In Linux systems, initrd is a scheme for loading a temporary root file system into memory, to be used as part of the Linux startup process. initrd and initramfs refer to two different methods of achieving this. Both are commonly used to make preparations before the real root file system can be mounted.
The booting process of Windows NT is the process run to start Windows NT. The process has been changed between releases, with the biggest changes being made with Windows Vista. In versions before Vista, the booting process begins when the BIOS loads the Windows NT bootloader, NTLDR. Starting with Vista, the booting process begins with either the BIOS or UEFI load the Windows Boot Manager, which replaces NTLDR as the bootloader. Next, the bootloader starts the kernel, which starts the session manager, which begins the login process. Once the user is logged in File Explorer, the graphical user interface used by Windows NT, is started.
The Prefetcher is a component of Microsoft Windows which was introduced in Windows XP. It is a component of the Memory Manager that can speed up the Windows boot process and shorten the amount of time it takes to start up programs. It accomplishes this by caching files that are needed by an application to RAM as the application is launched, thus consolidating disk reads and reducing disk seeks. This feature was covered by US patent 6,633,968.
The multi-stage booting process of Linux is in many ways similar to the BSD and other Unix-style boot processes, from which it derives.
DOS is a family of disk-based operating systems for IBM PC compatible computers. The DOS family primarily consists of Microsoft's MS-DOS and a rebranded version, IBM PC DOS, both of which were introduced in 1981. Later compatible systems from other manufacturers include DR DOS (1988), ROM-DOS (1989), PTS-DOS (1993), and FreeDOS (1998). MS-DOS dominated the IBM PC compatible market between 1981 and 1995.
A master boot record (MBR) is a special type of boot sector at the very beginning of partitioned computer mass storage devices like fixed disks or removable drives intended for use with IBM PC-compatible systems and beyond. The concept of MBRs was publicly introduced in 1983 with PC DOS 2.0.
The Windows 9x series of operating systems refers to the kernel which lies at the heart of Windows 9x. Its architecture is monolithic.
In computing, rebooting is the process by which a running computer system is restarted, either intentionally or unintentionally. Reboots can be either a cold reboot in which the power to the system is physically turned off and back on again ; or a warm reboot in which the system restarts while still powered up. The term restart is used to refer to a reboot when the operating system closes all programs and finalizes all pending input and output operations before initiating a soft reboot.
The booting process of Windows NT Setup before Vista works very similarly to the one of a regular Windows NT boot except that it runs from a CD-ROM. For this boot method to work, the BIOS must be compatible with the El Torito specification. The ISO 9660 file system on the install CD is not fully compatible with the standard. Although it is "Level 1", the file names don't have the file version appended to them. The boot image is of the "no emulation" type, 1 sector long and is loaded at segment 0x7c0. It can be extracted from an ISO image by using a file-extraction program such as 7-Zip or WinZip. The ISO image is also not hybridized like ISO images from most Linux distributions and therefore it does not contain any master boot record (MBR) which makes it unable to boot by just copying the image over a block device such as a pen drive.