.TH boot "" " "Device Driver"
.PC "Boot block for hard-disk partition/nine-sector diskette"
.PP
Several different programs are used to load \*(CO from
a floppy or hard disk into memory.
This process is called \fIbootstrapping\fR (from the old expression about
pulling one's self up by one's bootstraps) or \fIbooting\fR for short.
The program used depends upon whether one is loading \*(CO from a
hard-disk partition, from a 5.25-inch floppy disk, or from a 3.5-inch
floppy disk.
All of these programs are installed onto your computer
during normal installation.
.PP
.II mboot
.II "master boot program"
.II "booting^master boot program"
.B mboot
is the master boot program.
This is code that resides in the first 446 bytes of the first sector on the
hard disk.
Because this sector also contains the partition table for the hard disk,
.B mboot
is normally written to the hard drive only during installation and only by the
.B fdisk
utility.
.PP
.BR boot ,
.BR boot.fha ,
and
.B boot.fva
are variations of the same program.
.B boot
occupies the first sector of any bootable hard-drive partition.
.B boot.fha
occupies the first sector of a 5.25-inch, high-density floppy disk.
.B boot.fva
occupies the first sector of a 3.5-inch, high-density floppy disk.
.PP
.B boot
is normally copied to the root partition automatically during
installation by a command such as:
.DM
	/bin/dd if=/conf/boot of=/dev/at0a count=1
.DE
.PP
In another example, the following commands format and create a file system on
a high-density, 5.25-inch floppy disk:
.DM
	/etc/fdformat -v /dev/fha0
	/etc/mkfs /dev/fha0 2400
	/bin/cp /conf/boot.fha /dev/fha0
.DE
.PP
When invoked,
.B boot
loads for the tertiary boot program
.BR tboot .
This, in turn,
searches the root directory \*(Ql/\*(Qr for file \fBautoboot\fR,
which is the \*(CO kernel.
If it finds this kernel, \fBboot\fR loads and invokes it.
Otherwise, it gives the prompt \fI?\fR,
and you must type the name
of the operating-system kernel to load (typically, \*(QLcoherent\*(QR).
If \fBboot\fR cannot find the requested kernel or if an error occurs,
.B boot
does not print an error message, but re-prompts with \*(Ql?\*(Qr.
.SH Files
\fB/conf/boot\fR \(em Boot for AT partitions
.br
\fB/conf/boot.at\fR \(em Boot for AT partitions (linked to \fB/conf/boot\fR)
.br
\fB/conf/boot.atx\fR \(em AT master boot (linked to \fB/conf/mboot\fR)
.br
\fB/conf/boot.f9a\fR \(em Boot for single-density, nine-sector, 5.25-inch floppy disk
.br
\fB/conf/boot.fha\fR \(em Boot for 15-sector, 5.25-inch floppy disk
.br
\fB/conf/boot.fqa\fR \(em Boot for quad-density, nine-sector, 3.5-inch floppy disk
.br
\fB/conf/boot.fva\fR \(em Boot for 18-sector, 3.5-inch floppy disk
.br
\fB/conf/mboot\fR \(em AT master boot
.SH "See Also"
.Xr "device drivers," device_dr
.Xr fdisk, fdisk
.Xr mboot, mboot
.Xr mkfs, mkfs
.Xr tboot tboot
