.TH mboot "" "" "Device Driver"
.PC "Master boot block for hard disk"
.PP
To be bootable, a \*(CO file system must contain a boot block
(either 
.B boot
or 
.BR mboot ).
In addition, all hard disks must contain the master boot block
.B mboot
or an equivalent.
.PP
.B mboot
is the master boot block for a hard-disk drive.
It is compatible with, and therefore can replace, the IBM master boot block
installed by the \*(MD command
.BR FDISK .
It must be installed in the first sector of the hard disk, as follows:
.DM
	/etc/fdisk -b /conf/mboot /dev/at0x
	/bin/sync
.DE
.PP
.B mboot
searches its internal partition table (updated by the command \fBfdisk\fR)
for an active partition.
You can select an alternate partition by pressing 0 through 7 before
the system selects the active partition.
If the selected partition is of non-zero size
with a valid partition boot block,
\*(CO executes that partition's boot block.
Otherwise, the prompt
.DM
	Select partition [0-7]
.DE
.PP
appear, and the system waits for you to select the partition you want.
.SH Files
\fB/conf/mboot\fR \(em Hard-disk master boot block
.SH "See Also"
.Xr "boot," boot
.Xr "device drivers," device_dr
.Xr "fdisk," fdisk
.Xr "mkfs" mkfs
