October 13, 2008

### NAME

dosboot - boot NetBSD/i386 from DOS

### SYNOPSIS

dosboot [-u] [-c command] [-i] [path[ -adqsv]]

### DESCRIPTION

dosboot is an MS-DOS program. It is a boot loader for NetBSD/i386 designed to permit NetBSD to be booted directly from MS-DOS. By default, it boots a file with name ```NETBSD` in the current MS-DOS directory. dosboot shares common code with the standard boot loader, boot(8).

The recognized options are:

-u
  Boot from a UFS filesystem instead of an MS-DOS filesystem.

-c
  Execute command (see below).

-i
  Enter interactive mode. dosboot will present a prompt, allowing input of commands (see below).

```path`
  Specifies the kernel file. In MS-DOS mode (default) a normal MS-DOS filename (with or without drive specification) is accepted. In UFS mode (after -u or after a mode ufs command), a path in a NetBSD filesystem is expected. By default, the file is looked up in partition 'a' of the first harddisk. Another device or partition can be specified by prepending a block device name in terms of NetBSD, followed by a colon (see boot(8) and examples).

-adqsv
  Flags passed to the kernel, see boot(8).

The commands accepted after the -c flag or in interactive mode are:

Xo boot
  [device]: [filename] [-1234abcdmqsvxz] Boot NetBSD. See boot in boot(8) for full details.

dev[ device]
  Set the default device and partition for subsequent filesystem operations. Without an operand, print the current setting. This setting doesn't apply to MS-DOS mode.

help
  Print an overview about commands and arguments.

ls[```path`]
  Print a directory listing of ```path`, containing inode number, filename and file type. This command works in UFS mode only. path can contain a device specification.

mode fstype
  Switch filesystem type; fstype should be one of dos or ufs.

quit
  Leave the dosboot program and exit to MS-DOS.

dosboot is also installed in the release(7) hierarchy, under ```installation/misc/dosboot.com`.

### FILES

```/usr/mdec/dosboot.com`

### EXAMPLES

To boot a NetBSD kernel located on MS-DOS drive D, one would issue:

  `

      dosboot D:\NODOS\NETBSD

  `

To boot from a NetBSD floppy into single user mode, type e.g.:

  `

      dosboot -u fd0a:netbsd -s

  `

### SEE ALSO

release(7), boot(8), w95boot(8)

### HISTORY

The NetBSD/i386 dosboot command first appeared in NetBSD1.3.

### BUGS

dosboot assumes that the processor is in real mode at startup. It does not work well in the presence of MS-DOS extenders and memory managers.

dosboot does not run directly under Windows 95. See w95boot(8) for a method of starting NetBSD from Windows 95 using dosboot.

In UFS mode, files can only be loaded from devices known to the BIOS. The device names do not necessarily comply with the names later used by the booted NetBSD kernel.

In MS-DOS mode, no useful boot device specification is passed to NetBSD. It is necessary to have the root device hardwired into the kernel configuration or to enter it manually.