Copyright (c) 1997
Matthias Drochner. All rights reserved.
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@(#)boot_i386.8 8.2 (Berkeley) 4/19/94
.Dd February 17, 2017 .Dt DOSBOOT 8 x86 .Os .Sh NAME .Nm dosboot .Nd boot NetBSD/x86 from DOS .Sh SYNOPSIS .Nm .Op Fl u .Op Fl c Ar command .Op Fl i .Op Ar path Op Fl adqsv .Sh DESCRIPTION .Nm is an .Tn MS-DOS program. It is a boot loader for .Nx Ns Tn /x86 designed to permit .Nx to be booted directly from .Tn MS-DOS . By default, it boots a file with name
a NETBSD in the current .Tn MS-DOS directory. .Nm shares common code with the standard boot loader, .Xr x86/boot 8 .
p The recognized options are: l -tag -width "-adqsv" -offset 04n t Fl c Execute .Ar command (see below). t Fl i Enter interactive mode. .Nm will present a prompt, allowing input of commands (see below). t Fl u Boot from a UFS file system instead of an .Tn MS-DOS file system. t Ar path Specifies the kernel file. In .Tn MS-DOS mode (default) a normal .Tn MS-DOS filename (with or without drive specification) is accepted. In UFS mode (after .Fl u or after a c mode ufs command), a path in a .Nx file system is expected. By default, the file is looked up in partition .Sq a of the first hard disk. Another device or partition can be specified by prepending a block device name in terms of .Nx , followed by a colon (see .Xr x86/boot 8 and examples). t Fl 1234abcdmqsvxz Flags passed to the kernel, see .Xr x86/boot 8 . .El
p See .Xr x86/boot 8 for commands accepted after the .Fl c flag or in interactive mode.
p .Nm is also installed in the .Xr release 7 hierarchy, under
a installation/misc/dosboot.com . .Sh FILES
a /usr/mdec/dosboot.com .Sh EXAMPLES To boot a .Nx kernel located on .Tn MS-DOS drive D, one would issue: d -literal -offset indent dosboot D:\eNODOS\eNETBSD .Ed
p To boot from a .Nx floppy into single user mode, type e.g.: d -literal -offset indent dosboot -u fd0a:netbsd -s .Ed .Sh SEE ALSO .Xr release 7 , .Xr x86/boot 8 .Sh HISTORY The .Nx Ns Tn /x86 .Nm command first appeared in .Nx 1.3 . .Sh BUGS .Nm assumes that the processor is in real mode at startup. It does not work well in the presence of .Tn MS-DOS extenders and memory managers.
p .Nm does not run directly under .Tn Windows 95 .
p 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 .Nx kernel.
p In .Tn MS-DOS mode, no useful boot device specification is passed to .Nx . It is necessary to have the root device hardwired into the kernel configuration or to enter it manually.
Indexes created Tue Sep 23 22:09:46 GMT 2025