usage.8

操作系统设计与实现源码

     Remove /mnt/etc/issue to get rid of the "use setup" message  that  greets
     you  when  you boot, and edit the file /mnt/etc/fstab to name the devices
     Minix has been installed on.  In our example it should look like this:

          root=/dev/hd2a
          usr=/dev/hd2c

     Unmount the new root:

          umount /dev/hd2a

     Make it bootable:

          installboot -d /dev/hd2a /usr/mdec/bootblock boot

     The automatic script would now  set  the  rootdev  and  ramimagedev  boot
     variables.   You  can  do  this now using the edparams command, but it is
     easier to postpone it until the testing phase.  The settings should be:

          rootdev=hd2a
          ramimagedev=hd2a

  6. TESTING
     By now a new Minix system is present on your hard disk.  Time to  see  if
     it  works.   Leave the ROOT diskette in the drive and type halt.  You are
     now going to use the power of the Boot Monitor on the  diskette  to  boot
     the  Minix  partition on the hard disk.  Use the monitor command boot hd2
     to boot the primary partition Minix has been installed in.  (It is  "hd2"
     in  our  example.)  For a SCSI disk you will have to use a 'hd' name too.
     The monitor uses the BIOS, so you will have to treat  it  as  a  "normal"
     disk at this point.





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     The hard disk bootstrap is now showing the menu again.  You can type  '='
     to start Minix, but you probably want to change the boot parameters.  Hit
     ESC once more to get to the command prompt.  The command set  shows  what
     the  current parameters are.  Here is an example that shows how to make a
     menu to either start Minix or boot MS-DOS:

          minix(=,Minix) {boot}
          dos(d,MS-DOS) {boot hd1}
          save

     MS-DOS is assumed to be in the  first  partition  in  the  example  above
     (hd1).   When  finished  type menu to see if the menu looks right.  If so
     hit '=' to start Minix.

  7. ADDING PROGRAMS AND SOURCES TO /usr
     The setup command can also be used to add files from floppy sets  to  the
     system.   The USR.TAZ (programs and stuff), SYS.TAZ (system sources), and
     CMD.TAZ (commands  sources)  are  all  installed  relative  to  the  /usr
     directory, so the command to use three times is

          setup /usr

     Setup will ask for the size of data on the floppies, which is by  default
     simply  the  entire  floppy.   Don't worry if you see a few "File exists"
     errors while extracting, as some directories already exist.  You need the
     USR.TAZ  set  if  you  want  a  working Minix system, SYS.TAZ if you want
     recompile the system or study it,  and  CMD.TAZ  if  you  also  want  the
     sources  of  the  simple  commands.   On a disk space starved machine you
     could opt to do without the commands sources, as they are not  absolutely
     necessary to understand Minix.

     If your machine does not have enough memory to run setup /usr  then  type
     these commands manually:

          cd /usr
          vol /dev/fd0 | uncompress | tar xvfp -

  8. NAMES
     A standalone machine will have to be given a name.  As root type

          echo name >/etc/hostname.file

     to change the host name of your machine to name.

  9. ACTIVE ON BOOT
     You  may  want  to  make  the  Minix  partition  active  so  that  it  is
     automatically  booted.   With  DOS  fdisk or Minix part, mark the primary
     partition that contains Minix active.  Using the menu  you  made  earlier
     you  can  boot  either  Minix  or  DOS  at  a keypress.  You can even set
     timeouts.  To boot Minix automatically after 5 seconds:


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          main() {trap 5000 minix; menu}

     See monitor(8) for all the details on the monitor.

     If you don't trust this then you can rig up a  diskette  that  boots  the
     Minix partition when left in the drive:

          installboot -m 2 /dev/fd0 /usr/mdec/masterboot

     The number 2 indicates the hard disk partition that must be  booted,  you
     can use the numbers 1 to 9 for hd1 to hd9.

  10. DEVICES
     A crash course on the Minix devices in /dev:   The  two  hard  disks  are
     named  hd0  and hd5.  These "multiple of five" devices address the entire
     hard disk, from  the  first  to  the  last  byte.   Each  disk  has  four
     partitions,  for  disk 0 they are hd1, hd2, hd3, and hd4.  And for disk 1
     they are named hd6, hd7, hd8, and hd9.  These partitions may contain file
     systems,  hd1  often contains the MS-DOS "C:" file system.  Minix can use
     these partitions for file systems too, but you can also partition one  of
     these  "primary  partitions"  into  four  so-called "subpartitions".  The
     subpartitions of hd1 are named hd1a, hd1b, hd1c,  and  hd1d.   The  other
     partitions  may have four subpartitions that are named in the same way by
     adding a letter from a to d.  So one disk may have four  partitions,  and
     16 subpartititions total.  SCSI disks are named in the same way, from sd0
     to sd39d for all possible devices for all eight SCSI  targets.   The  two
     floppy  disks are fd0 and fd1.  Each may have four partitions named fd0a,
     fd0b, ...  fd1d.  The command MAKEDEV knows  how  to  make  devices,  and
     DESCRIBE  can  tell  you  what an unknown device may be, or even what all
     devices in  /dev  may  be  if  called  without  arguments.   Devices  are
     described  fully  in dev(4), and in the device specific manual pages like
     fd(4) and hd(4).

  11. EDITORS
     The editors available are elvis  (a  vi  clone),  elle  (a  simple  emacs
     clone),  and the old Minix mined editor.  Of these editors only elvis can
     recover your file after a system  crash.   Only  mined  is  available  at
     installation  time.   (All you need to know about mined right now is that
     CTRL-X gets you out of it.)

  12. INSTALLING ON A SCSI DISK
     Using a disk other than a hd disk complicates things  a  bit.   The  Boot
     Monitor  uses  the  BIOS,  so it names all disks with hd names.  So it is
     boot hd1 to boot partition 1, and ramimagedev=sd2a to tell Minix its root
     partition.   If you have both a normal and a SCSI disk then the disks may
     be hd0 and hd5 to the Monitor, and hd0 and sd0 to Minix.






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  13. NATIONAL KEYBOARDS
     The  directory  /usr/lib/keymaps  contains  keymap  tables  for   several
     national keyboards.  If you have a German keyboard for instance, then

          loadkeys /usr/lib/keymaps/german.map

     will load the German key translation  table  into  the  keyboard  driver.
     Copy  the  map  to  /etc/keymap once Minix is installed on the hard disk,
     because having to type a key sequence like one of these:

          loadkezs -usr-lib-kezmaps-german.map
          loqdkeys =usr=lib=key,qps=french.,qp

     on a reboot gets a bit annoying after a while.  Send corrections and  new
     keymaps  to  the  person  named  below.  (Do not send a Dutch keymap, buy
     yourself a real keyboard instead.)

SUGGESTIONS
     Below are a few useful suggestions.  Some of the information  can  be  of
     use in other situations than described here.

  14. VIRTUAL CONSOLES
     Hold down the ALT key and press the left or right arrow key, F1,  or  F2.
     This  switches  the console between two login sessions.  (Unless you have
     an old mono adapter, because virtual consoles sit in video memory, and  a
     mono adapter only has memory for one.)

     Note that kernel messages, including function key output, only appear  on
     the  first  console.   This  may  be  confusing,  but  it keeps the other
     consoles clean.

  15. LOW ON MEMORY
     The normal installation requires that you have enough memory for a  large
     RAM disk.  You can still install Minix normally if you either have a high
     density diskette drive for a combined root+usr floppy, or  you  have  two
     floppy  drives  of  at  least 720 kb.  Before booting you have to set the
     variable rootdev to the same value as ramimagedev.  This is slower then a
     RAM disk, but saves a lot of memory.

     The automatic installation script knows how to handle this new situation.
     If you install manually then you have to use

          cpdir -vx / /mnt

     to copy the root device to disk.  When it is time to fill  /usr  and  you
     only  have  one  floppy drive then hit DEL to get out of the installation
     script and reboot as described in "TESTING".  You  can  then  finish  the
     installation manually.




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  16. LOW ON MEMORY AND ONLY ONE 720 KB FLOPPY DRIVE
     If you only have one 720 kb floppy drive and your system is low on memory
     then  you  can  use the TINYROOT boot image.  This image contains a small
     kernel with only the BIOS disk driver, and a small root file system.  You
     can  use  this disk to boot your machine.  Use the normal ROOT to install
     the root file system.  Keep booting your machine with TINYROOT until  you
     have  compiled  a  small  kernel  for  your system.  Use the rootdev boot
     variable to select the hard disk root file system.  Do not  use  TINYROOT
     for anything other than booting, always use ROOT when mentioned.

  17. FLOPPY DRIVE 1 IS A HIGH DENSITY DRIVE
     If you would like to install from floppy drive 1 then you need to copy at
     least one sector from the USR image onto a diskette for drive 0.  The USR
     bootstrap has been rigged to boot the other drive.

  18. INSTALLING ON A SECOND HARD DISK
     Minix doesn't care if it is installed on the second disk of a system with
     two  disks.  The only problem is to get it booted.  You can either rig up
     a diskette to boot Minix as shown earlier, or you can use the same  trick
     on the first disk.  The command

          installboot -m 5 /dev/hd0 /usr/mdec/masterboot

     will lock the first disk into booting the second disk.   Note  that  this
     command modifies the disk outside a Minix partition, overwriting a bit of
     code that has likely been put there by DOS fdisk.  First verify that  the
     Boot  Monitor  can  boot  a  DOS partition, because then the Minix master
     bootstrap can do it too.

  19. LOTS OF MEMORY ON A 286
     You will have a hard time making Minix run out of 3  Mb  memory.   Memory
     you  can  spare  can  be used for a "second level block cache" on the RAM
     disk.  The File System uses the second level cache  to  store  copies  of
     disk blocks that are pushed out of the normal (primary) block cache.  The
     size of the primary cache is compiled into the FS server, but the size of