monitor.8

minix操作系统最新版本（3.1.1）的源代码

will then execute the
.B AT
function above.
.RE
.SP
\fIname\fP(\fIkey\fP,\fItext\fP) \fIcommand\fP
.RS
User defined menu option.
.br
This variant may be used to make any menu entry you like:
.SP
.RS
dos(d,Boot MS-DOS) boot d0p0
.RE
.SP
.I Text
may be anything, even parentheses if they match.
.RE
.SP
.I name
.RS
Call function.
.br
If
.I name
is a user defined function then its value is expanded and executed in place of
.IR name .
Try a recursive one like 'rec() {rec;xx}' one day.  You can see the monitor
run out of space with nice messages about using
.BR chmem (1)
to increase it's heap.
.RE
.SP
\fBboot\fP [\fB\-\fP\fIopts\fP]
.br
\fBboot\fP \fIdevice\fP
.RS
Boot MINIX 3 or another O.S.
.br
Without an argument,
.B boot
will load and execute the MINIX 3 image named by the
.B image
variable.  With options the variable
.B bootopts
is first set to
.BI \- opts
before MINIX 3 is started, and unset when Minix returns.  With a
.I device
argument,
.B boot
loads the boot sector of
.I device
into memory and jumps to it, starting another operating system.  You would
normally use partitions on the first hard disk for this command (d0p[0\-3]),
using d0 will also work (choosing the active partition).  One can also boot
devices on the second hard disk (d1, d1p[0\-3]) if the bootstrap writer did
not hardwire the disk number to disk 0.
.br
Some Operating Systems can only be booted from the active partition, if
you use a '*', e.g.
.BR "boot *d0p2" ,
then partition 2 is first made active.  You'll then need to use
.SP
.RS
.BI "installboot \-m /dev/c0d0 /usr/mdec/jumpboot" " keys"
.RE
.SP
with
.I keys
chosen so that MINIX 3 is booted at startup.  (See
.BR installboot (8).)
.RE
.SP
\fBctty\fP \fIn\fP
.RS
Copies output to and takes input from serial line
.I n
(0-3) at 9600 baud, 8 bits, no parity.
This allows you to control a MINIX 3 system remotely through an RS-232
connection.
.RE
.SP
\fBdelay\fP [\fImsec\fP]
.RS
Delay (500 msec default).
.br
Fast booting speed was one of the objectives when this program was created,
so a hard disk boot usually takes only a fraction of a second.  If you need
some time (to hit Escape, or stare at the numbers) you can use
.B delay
to make the monitor pause for a specified number of milliseconds.
.RE
.SP
\fBecho\fP \fIword\fP ...
.RS
Print these words.
.br
Used to display messages, like the startup banner.  Echo normally prints
the words with spaces in between and a newline at the end.  Echo understands
special '\e' escape sequences as follows:
.RS
.SP
\e	(At the end) Don't print a newline.
.br
\en	Print a newline.
.br
\ev	Print the monitor's version numbers.
.br
\ec	Clear the screen.
.br
\ew	Wait until a RETURN is typed
.br
\e\e	Print a backslash.
.RE
.RE
.SP
\fBls\fP [\fIdirectory\fP]
.RS
List contents of a directory.
.br
Useful when looking for kernel images.
.RE
.SP
.B menu
.RS
Menu driven startup.
.br
This command allows you to execute functions defined with a
.IR key .
If no menu functions have been defined then
.B menu
will use this one hidden built-in function:
.SP
.RS
*(=,Start Minix) boot
.SP
.RE
Kernel selecting functions only add new options to this set, but if you
define a two argument function yourself then the above one is no longer
shown, allowing you to customize the menu completely.  Your first
function definition should therefore be one that starts MINIX 3.
.SP
Menu entries are shown in the same order as
.B set
shows them.  If you don't like the order then you have to unset the
functions and retype them in the proper order.
.SP
If you type a key then a scheduled trap is killed and the appropriate menu
function is executed.  If you need more time to choose then hit the
spacebar.  A key not on the menu also kills a trap, but does nothing more.
.RE
.SP
.B save
.RS
Save environment.
.br
This will save all the environment variables and functions with nondefault
values to the parameter sector (the second sector on the boot device), so
they are automatically set the next time you boot the monitor.
.RE
.SP
.B set
.RS
Show environment.
.br
Show the current values of the environment variables and functions.  Default
values are shown between parentheses to distinguish them from values that
were explicitly set.
.RE
.SP
\fBtrap\fP \fImsec\fP \fIfunction\fP
.RS
Schedule function.
.br
Schedules a function to be executed after
.I msec
milliseconds.  Only the monitor mode cannot be interrupted, a scheduled trap
is killed when the prompt is printed.  Example:
.SP
.RS
main() {trap 10000 boot; menu}
.RE
.SP
This gives you 10 seconds to choose a menu option before MINIX 3 is booted.
.RE
.SP
\fBunset\fP \fIname\fP ...
.RS
Unset environment variables.
.br
Removes the named variables and functions from the environment, and sets
special variables back to their default values.  This is also the only way
to remove the "device name translation" property from a variable.
.RE
.SP
\fBexit\fP
.RS
Exit the monitor.
.br
Reboot the machine, exit to MINIX 3 or exit to DOS as appropriate.
.RE
.SP
\fBoff\fP
.RS
Turn the PC off.
.br
If the PC supports power management then turn it off, otherwise
print some error messages and do nothing.
.RE
.SP
\fB{\fP \fIcommand\fP; ... \fB}\fP
.RS
Bundle commands.
.br
Treat a number of commands as a single command.  Used for function
definitions when a function body must contain more than one command.
.RE
.SH DEVICES
The MINIX 3 kernel can't do anything with device names, so they have to be
translated to device numbers before they are passed to the kernel.  This
number is found under the st_rdev field (see
.BR stat (2))
of the file on the boot file system.  The monitor will look for the device
file with the working directory set to '/dev'.  If it can't find the device
name then it will translate names like 'ram', 'fd1', 'c0d1p0', 'c1d0p2s0',
and even the obsolete 'hd2a' to what it itself thinks the numbers should be.
.PP
The special name
.B bootdev
is translated to the name of the device booted from, like 'fd0',
or 'c0d0p1s0', and then searched for in /dev.
.B Bootdev
can only be translated to a device for the first controller, and only if
the disks on that controller are numbered without "gaps".  (The master
device on the second IDE channel is always d2 on MINIX 3.  The BIOS will
call it disk 0, 1, or 2 depending on the number of disks on the first
IDE channel.)
.SP
Controller numbers are meaningless to the BIOS, so everything is assumed to
be attached to controller 0.  You can omit
.B c0
for device names, and it is best to always omit
.B c0
for the
.B boot
command, and to always use the full name for variables passed to MINIX 3.
.SH EXTENSIONS
A few extensions have been made to this program for kernel hackers.  They
may be triggered by setting bits in the flags word in the kernel startup
code (the mpx file.)  The flag bits are:
.TP 10
0x0001
Call kernel in 386 mode.
.TP
0x0002
Do not make space for the bss areas of processes other than the kernel.
.TP
0x0004
Use the stack size set by
.BR chmem (1).
.TP
0x0008
Load MM, FS, etc. into extended memory.
.TP
0x0010
No need to patch process sizes into the kernel.
.TP
0x0020
The kernel can return to the monitor on halt or reboot.
.TP
0x0040
Offer generic BIOS support instead of just INT 13 (disk I/O).
.TP
0x0080
Pass memory lists for free and used memory (processes).
.TP
0x0100
Kernel returns monitor code on shutdown in boot parameters array.
.SH "SEE ALSO"
.BR controller (4),
.BR installboot (8),
.BR usage (8),
.BR boot (8),
.BR dosminix (8).
.SH BUGS
The
.B delay
command will hang forever on the original IBM PC (not the XT!).  Not that it
matters, as everything takes forever on that box.
.PP
By redefining
.B leader
one can easily hide the identity of this program.
.SH ACKNOWLEDGMENTS
Earl Chew, for the inspiration his ShoeLace package provided, unless he wants
to file a "look and feel" suit against me, then I will say I modeled it after
the Sun ROM boot monitor, which is also true.
.SH AUTHOR
Kees J. Bot ([e-mail])
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.\" $PchId: monitor.8,v 1.11 2002/02/27 19:36:34 philip Exp $