Demacs version 1.2.0 (1991/12/12)
DOS version of GNU Emacs
Manabu Higashida
manabu@sigmath.osaka-u.ac.jp
Osaka University, JAPAN
and
HIRANO Satoshi
hirano@tkl.iis.u-tokyo.ac.jp
University of Tokyo, Japan
Copyright 1991 Halca Computer Science Laboratory TM
Copyright 1991 Manabu Higashida
Demacs is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License version 1 as
published by the Free Software Foundation.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License (this package includes it as file 'copying')
for more details.
Demacs version 1.2.0
********************
Demacs---386/486 DOS version of GNU Emacs.
Current Version
===============
Demacs is currently based on GNU Emacs version 18.55 (partly 18.57).
Demacs version itself is 1.2.0 (1991/12/12).
## Command: demacs-version
Return string describing the version of Demacs that is running.
Platforms
=========
Hardware
386/486 based DOS machines---IBM PC and its compatible, AX, J-3100,
or NEC PC-9801, High resolusion PC-98 and its compatible EPSON PC-386
Software
MSDOS 3.0 or later
XMS manager (`HIMEM.SYS') and VCPI memory manager (`EMM386.EXE',
`QEMM', etc.) compatible.
Demacs does not support DPMI, thus it can not be used with extended
mode on Windows.
Bug Report
==========
When you have troubles with using Demacs, please follow the following
steps before inquire us.
First, read this README and the online-manuals (with Info Browser) to
find answers. Next, consult to Emacs experts around you or on the
networks. In case you decide to send a mail to the authors, you must
read "Bugs" section in the Emacs manual before sending the mail.
Suggestions and bug fixes are welcome with next address.
demacs-bugs@sigmath.osaka-u.ac.jp
If you want to know current status about Demacs, send empty mail to
next address.
demacs@sigmath.osaka-u.ac.jp
We will reply your mail with latest information, automatically.
Installation
************
Contents of This Distribution Kit
=================================
The package consists of two archives; `dem120e.lzh' and `dem120s.lzh'.
You need LHarc or LHa utility to unpack these archives. Don't forget to
use `/mx' switches with `-x' option to unpack them. For example do as
following.
lharc x /mx dem120e.lzh
lharc x /mx dem120s.lzh
And similarly apply these options to the archives which are contained by
them.
After unpacking, following files will appear.
`dem120e.lzh' (executables)
readme this file
demacs.tex texinfo version of `readme'
demacs.dvi compiled `demacs.tex' by TeX
copying GNU General Public Licence
copying.dj DJGCC copyright notice
termcap sample termcap file
_emacs sample startup file
bin\demacspc.exe DOS extender for IBM PC and its compatible machines
bin\demacs98.exe DOS extender for PC-9801, PC-386 series
bin\demacs demacs object file (stripped)
bin\temacs `plain' demacs object file (stripped)
etc.lzh emacs documentation string file and etc.
lisp.lzh includes lisp files which are necessary to run
edired.lzh enhanced dired-mode
`dem120s.lzh' (source files)
src\diffs.lzh includes only different files from the original
lisp\diffs.lzh includes only different files from the original
go32_98\source.lzh PC-9801 version go32 DOS extender from DJGCC
go32_pc\source.lzh IBM PC version go32 DOS extender from DJGCC
NOTE:
This package only includes lisp files which are modified for Demacs.
Original and/or other useful lisp stuff can be obtained from various FTP
sites (for example `ftp.sigmath.osaka-u.ac.jp') or from:
Free Software Foundation, Inc.
675 Mass Ave, Cambridge, MA 02139, USA
How to Install
==============
Demacs requires special version of `go32.exe' DOS extender. This package
includes it with its name `bin\demacspc.exe' for IBM PC or
`bin\demacs98.exe' for PC-9801 series. You should use one of them with
renameing to `demacs.exe'.
Since `go32.exe' which came along with the package of DJ's GCC/G++
version 1.05 can not handle `Ctrl-C' properlly, we modified it to work
correctly. And we made some changes to be able to handle more DOS
function call, and enhanced its memory management strategy (detail, see
below).
Installation procedure is quite easy.
1. If your system is IBM PC variant (including AX and J-3100 series),
copy `bin/demacspc.exe' to the directory in PATH with its name
`demacs.exe'.
If your system is NEC PC-9801 or EPSON PC-386 series, copy
`bin/demacs98.exe' to the directory in PATH with its name
`demacs.exe'.
2. Copy `bin\demacs' in the same directory with `demacs.exe'.
3. Create `lisp' and `etc' directory in `\lib\emacs' directory.
4. If you want to use lisp library, get original lisp files from
somewhere and copy them in `\lib\emacs\lisp' directory. Then unpack
`lisp.lzh' in `\lib\emacs' directory.
5. Unpack `etc.lzh' in `\lib\emacs' directory.
6. Set TERM environment variable for your system (See following example).
7. Set TERMCAP variable if `termcap' file is not stay under `\etc'.
8. Prepare your `_emacs' (`.emacs' on Unix system) under your HOME
directory if you need it.
Sample Session to Install
=========================
C> copy bin\demacspc.exe \tools\bin\demacs.exe (IBM PC, AX, J-3100)
C> copy bin\demacs \tools\bin
or
C> copy bin\demacs98.exe \tools\bin\demacs.exe (PC-9801, PC-386)
C> copy bin\demacs \tools\bin
C> mkdir \lib\emacs
C> mkdir \lib\emacs\lisp
C> mkdir \lib\emacs\etc
C> copy lisp.lzh \lib\emacs
C> copy etc.lzh \lib\emacs
C> cd \lib\emacs
C> lharc x /mx lisp.lzh
C> lharc x /mx etc.lzh
C> del lisp.lzh
C> del etc.lzh
C> set TERM=ibmpc (IBM PC)
or
set TERM=j3100 (J-3100)
or
set TERM=pc98 (PC-9801, PC-386)
C> set TERMCAP=c:\etc\termcap (IBM PC, J-3100)
or
set TERMCAP=a:\etc\termcap (PC-9801, PC-386)
C> set HOME=c:\home (your startup file '_emacs' is placed)
Invocation
**********
Environment Variables
=====================
`C>set GO32TMP=c:/tmp'
directory where swapped files are placed (see DJGCC's readme).
`C>set TERM=ibmpc'
entry name of `termcap'.
`C>set TERMCAP=c:/etc/termcap'
directory where `termcap' file are placed.
`C>set HOME=c:/home'
directory where startup file `_emacs' are placed.
`C>set TZ=JST-9'
time zone.
`C>set USER=manabu'
your name up to 8 characters.
`C>set EMACSLOADPATH=d:/emacs/lisp'
set lisp load path if you don't use standard path `/lib/eamcs/lisp'.
`C>set EMACSEXECPATH=d:/emacs/etc'
set etc load path if you don't use standard path `/lib/emacs/etc'.
`C>set DEMACS_KEEP=1024'
amount of extended memory to keep (detail, see below).
`C>set SHELL=c:\command.com'
your command interpreter path.
Options of DOS Extender `demacs.exe'
====================================
`-keep [NUM]'
When `demacs.exe' invokes a child process, `demacs.exe' does not
swap out contents of the extended memory to a disk. If NUM is
specified, `demacs.exe' uses up to NUM killo bytes of extended
memory.
You should use this option with XMS or VCPI memory manager. If not, may
cause violation.
More about `-keep' opiton:
`demacs.exe' provides virtual memory mechanism. If an application (e.g.
Demacs) requires more memory than equipped real memory, `demacs.exe'
write out a portion of real memory to a disk in order to make a free
memory, then `demacs.exe' assigns the new free memory to the
application. This is called "swapping".
Swapping does not only happen when real memory shortage, but also
happens when `demacs.exe' calls a child process. That is, before
execution of the child process, `demacs.exe' swapps out all of allocated
memory to a disk so that the child process can use memory.
Unfortunatly, swapping takes very long time because Demacs is a huge
program.
In order to eliminate this swapping time, our `demacs.exe' can take
`-keep' option. `-keep' option requests to `demacs.exe' NOT to swap out
contents of extended memory (conventional memory (less than 640KB) is
always swapped out).
In case you use XMS driver such as `himem.sys', since `demacs.exe'
obtains all of free extended memory at startup, a child process can not
use any extended memory (Remember GCC/G++ requires extended memory).
You can reserve extended memory for the child process by following NUM
to `-keep', e.g. ``-keep 1024''. NUM which is killo byte unit number
limits amount of usage of extended memory by `demacs.exe'. If less
amount of extended memory is available than NUM at startup, `demacs.exe'
uses all of extended memory.
Otherwise in case you use VCPI driver such as `QEMM' or `EMM386',
`demacs.exe' gets extended memory on demand basis. ``-keep NUM'' limits
amount of extended memory used by `demacs.exe' to NUM killo bytes.
The following table shows a brief summary.
| swap out |
| extended memory |
| at fork child | extended memory for child
--------------+-------------------+------------------------------
without -keep | YES | all of extended memory at startup
-keep | NO | nothing
-keep <num> | NO | extended memory at startup - num
Too small NUM makes Demacs slower. I recommend to set NUM at
least 512.
Example (Demacs uses 1024KB extended memory):
demacs.exe -keep 1024
NUM can be also specified by DEMACS_KEEP environment variable. If both
environment variable and option are specified, option has priority. If
you don't need to specify NUM with `-keep' option, specify the value `0'
with this environment variable.
Options of Demacs
=================
Type `demacs [-keep [NUM]] [options]' to invoke Demacs. If you need more
information, see "GNU Emacs manual".
Features
********
File Type: Text or Binary Translation
=====================================
Translation Mode
----------------
On MS-DOS file system, a line is ended with CR (0x0d)/LF (0x0a)
characters and a file is ended with `Ctrl-Z' character. But on UNIX file
system, a line is ended with only LF character, and end of data meas end
of file.
Treating "binary files" which contains `Ctrl-Z' characters and for
compatibility to UNIX file system, C I/O library on MS-DOS has following
two translation mode which control these characters.
* Text mode translation
* Binary mode translation
With text mode translation, on reading, CR/LF code are translated to CR
and reading is terminated as soon as `Ctrl-Z' appears. On writing, LF is
added to CR and `Ctrl-Z' is added to end of file.
With binary mode translation, no code is translated.
Demacs supports these two translation mode, and manage them on each
buffer. You can find current translation mode of the buffer from file
type mnemonic on the mode line.
--**-Emacs: demacs.tex (T:Texinfo)--42%---------------
^
File type mnemonic means
`T'
Text mode translation.
`B'
Binary mode translation.
We call this translation mode which is managed on each buffer "file
type".
Demacs Buffer Management
------------------------
File Type of Each Buffer
........................
File type of each buffer is stored on buffer-local `file-type' variable.
To set the value of `file-type' use the `set-file-type' function.
The default value of `file-type' is the value of `default-file-type'
variable. To set its value, use the `set-default-file-type' function.
## Local Variable: file-type
`0'
Text mode translation.
`1'
Binary mode translation.
## Command: set-file-type TYPE &optional BUFFER
This function sets buffer-local `file-type' variable of BUFFER to
TYPE. The argument BUFFER defaults to the current buffer. The value
of TYPE is one of followings.
`0' or `'text' or `"text"'
Specify the buffer's file type to text mode.
`1' or `'binary' or `"binary"'
Specify the buffer's file type to binary mode.
## Global Variable: default-file-type
The value of this grobal bariable is the default value of
buffer-local `file-type' variable.
## Command: set-default-file-type TYPE
This function sets the value of `default-file-type' variable to
TYPE. The value of TYPE is one of followings.
`0' or `'text' or `"text"'
Specify the buffer's file type to text mode, by default.
`1' or `'binary' or `"binary"'
Specify the buffer's file type to binary mode, by default.
Buffer Creation
...............
When creating a new buffer, Demacs set the buffer's local variable
`file-type' to the value of the `default-file-type' variable.
Reading Files into Demacs Buffers
---------------------------------
Using the `define-file-name-file-type' function, you can define file
type associated with file name.
For example,
(define-file-name-file-type "\\.mem$" 'binary)
defines that file type of files having extention `.mem' is binary.
By default, the files ending with `.elc', `.obj', `.exe', `.com',
`.lib', `.sys' (except `config.sys'), `.chk', `.o', `.a' and `.out' are
defined as binary file type. This is defined in `demacs.el'.
## Function: define-file-name-file-type FILENAME TYPE
This function defines file type associate with file name. FILENAME
is regular expression or `nil'. `nil' matches any file anme. TYPE
is file type.
## Function: find-file-type-from-file-name FILENAME
This function returns file type which associate with FILENAME
defined by `define-file-name-file-type' function. If no file type
is defined, this returns a value of `default-file-type'.
Inserting Files into Buffers
............................
When inserting a file already visiting buffer, Demacs calls the
`find-file-type-from-file-name' function with file name of target file
as its argument, and set return value to file type of the buffer.
Visiting Files and Reading
..........................
When visiting a file and reading into a buffer, Demacs calls the
`find-file-type-from-file-name' function with file name of target file
as its argument, and set return value to file type of the buffer.
Creating Files and Visiting
...........................
The `find-file-not-found-set-file-type' function is appended to
the `find-file-not-found-hooks' variable. This means that
`find-file-not-found-set-file-type' is called when the visiting
file not exists.
This function calls internally the `find-file-type-from-file-name'
function with target name as its argument and set return value to file
type of the buffer.
Writing Buffers into Files
--------------------------
When writing a buffer into a file, Demacs set translation mode to file
type of the buffer.
Process I/O
-----------
Demacs communicate with external process (child process) using temporary
file. The `default-file-type' variable is used as file type of the
buffer which displays result.
"8bit clean" Display Mode
=========================
Demacs supports so called "8bit clean" display mode, which displays 8bit
dirty characters as it is instead of backslashed or arrowed form.
If you want use this mode, execute command `toggle-pass8-mode'. You can
find in mode line whether the buffer is in "8bit clean" display mode.
--**-Emacs: foo.bar (T:Fundamental Pass8)--28%---------------
^^^^^
To return ordinary display mode, again execute command
`toggle-pass8-mode'.
If you want create a buffer always in "8bit clean" display mode, place
(setq-default pass8-mode t)
in your startup file.
## Local Variable: pass8-mode
If this variable is `*Non-nil', Demacs displays 8bit dirty
characters as it is. Default value is `nil'.
## Command: toggle-pass8-mode
Set/Unset the buffer local variable `pass8-mode'.
8086 Software Interrupt
=======================
Function `int86' generate 8086 software interrupt. DOS Extender
`demacs.exe' not handle all interrupts, so some interrupts are treated
as exception and may cause violation. Use this carefully.
Use this function like this.
int
GetDisk ()
{
union REGS regs;
regs.h.ah = 0x19; /* 25 */
int86 (0x21 /* 33 */, ®s, ®s);
return regs.h.al;
}
C funtion to get current disk number may write in Demacs as follows:
(defun get-disk ()
(let ((regs (make-register)))
(set-register-value regs 'ah 25) ; 0x19
(int86 33 regs) ; 0x21
(register-value regs 'al)))
## Function: make-register
Generate instance of register type which is passwd to `int86'
function.
## Function: register-value REGISTER NAME
Get the value of REGISTER's NAME. NAME is one of followings.
`'ax'
`ax' register
`'bx'
`bx' register
`'cx'
`cx' register
`'dx'
`dx' register
`'si'
`si' register
`'di'
`di' register
`'cflag'
carry flag
`'flags'
flag register
or
`'al'
lower byte of `ax' register
`'ah'
upper byte of `ax' register
`'bl'
lower byte of `bx' register
`'bh'
upper byte of `bx' register
`'cl'
lower byte of `cx' register
`'ch'
upper byte of `cx' register
`'dl'
lower byte of `dx' register
`'dh'
upper byte of `dx' register
## Function: set-register-value REGISTER NAME VALUE
Set REGISTER's NAME to VALUE. VALUE is unsigned integer.
## Function: int86 INTNO REGISTER
Generate 8086 software interrupt of number INTNO with REGISTER.
This returns set of register value.
Machine Specified Features
==========================
New lisp variable `dos-machine-type' is introduced for support various
machines.
## Global Variable: dos-machine-type
Set one of `ibmpc', `j3100', `pc98' to select machine specific
code.
IBM PC
------
If you use IBM PC, evaluate `(setq dos-machine-type 'ibmpc)', then
`Ctrl-SPACE' will generate null code and `meta-flag' will works.
Toshiba J-3100
--------------
If you have J-3100, evaluate `(setq dos-machine-type 'j3100)', then
following functions will be abailable in addition to IBM PC features.
set-cursor-mode
get-screen-mode
set-cursor-mode
set-keyclick
set-screen-mode
See `lisp/dos-fns.el' for more information.
NEC PC-9801, EPSON PC-386
-------------------------
If you have PC-9801 or EPSON PC-386, evaluate `(setq
dos-machine-type 'pc98)', then following functions will be abailable.
pc98-assign-special-key
pc98-cancel-special-key
See `src/dosfns.c' for more information.
Other Demacs Features
=====================
1. Filename Completion
Demacs provides filename completion feature. Filename may include
drive name in its front. For example, we assume the current
directory is `c:/tools/emacs' and there is a file `d:/config.sys',
under this condition `C-x C-f' invokes `find-file' function then
the function prompts like
Find file: c:/tools/emacs/
at this point your typing of `d:/confi' and TAB key causes:
a:/tools/emacs/d:confi^I -> d:/config.sys [sole complete]
2. Child Process
Function `suspend-emacs' calls sub shell. Try `C-z' and a new
command shell is invoked.
Function `call-process' calls sub shell like `suspend-emacs' but
its stdout is redirected to a temporary file and it will be
displayed after completion of the process. Try `M-!'. But don't
call programs which require input from keyboard, because Demacs
can't response to them.
3. Enhanced Dired
This package includes enhanced dired-mode by Sebastian Kremer and their
dos ported codes which works without UNIX compatible `ls.exe'.
To use this, extract `edired.lzh' to your lisp directory and put
lines
(setq dired-mode-map nil)
(load "emacs-19")
(autoload 'dired "dired" nil t)
to your startup file (`direddos.elc' is loaded from `dired.elc').
If you have `ls.exe', append
(setq dired-load-hook
'(lambda ()
(setq dired-ls-program "ls")))
to your startup file. If you use Demacs with `-keep' option, this
configration works faster than former one.
You can get more infomation from `dired.README' and its document
string.
Restrictions
************
* Demacs does not support asyncronous process. Therefore you can not use
standard `compile.el', `shell-mode.el' and etc. I think it's
too painful, so, customized `compiled.el' and `dired.el' are
provided. See lisp directory.
* `Ctrl-G' can't generate inturrupt signal. So you can't quit lisp-form
like this:
(while t ())
You shoud use the following form instead of it.
(while (not (input-pending-p)) ())
* Demacs backup filename convension is following.
Base backup filename is made from following rule.
foo -> foo.~
foo.c -> foo.c~
foo.tex -> foo.te~
Since DOS filename rule (8.3) is too tight, numeric backup such like
`foo.c.~2~' can not be used.
Similarly auto save filename is made from following rule.
abcdefgh -> #abcdefg.#
foo.c -> #foo.c#
foo.tex -> #foo.te#
Similarly, auto-save file name is created.
* If you don't configure XMS or VCPI driver and invoke Demacs with
`-keep' option, child process Demacs (or go32 application) will
*not* work correctly.
* If you use VCPI manager and you have less extended memory than
300KB, Demacs will hang up or being to work *VERY* slowly. Plese
give Demacs much memory if you met this.
Compilation
***********
If you wish to recompile Demacs, 'GJ's GCC/G++' (GNU C compiler for DOS)
and original Emacs source are required.
Diffs to the original Emacs source files are included in
`src\diffs.lzh'. Unpack the archive. The files in `diffs.lzh' are not
`diff' form but they are full source files, so you need not to apply
patch. You may need to alter makefile.
Then run `make -f xmakefile all' command. Make generates `temacs' and
`demacs'. Caution! just `make' will destroy `xmakefile'. I prepared
`xmake.bak' for you.
Note that all modifications are embeded by `#ifdef MSDOS' and
`#endif MSDOS', so you may follow my modifications easily. Machine
specified codes are embedded in similar flags.
*.h *.c (C source files)
|
------| make
| |
| V
| temacs (plain demacs) and lisp/*.el (lisp source files)
| |
| | go32 temacs -batch -l loadup.el dump
|---->|
V
xemacs
Provided `bin/temacs' enables you to reconfigure demacs without
recompilation. After editing lisp sources which are loaded up by
`loadup.el', run `go32 temacs -batch -l loadup.el dump'.
Terminal Specified Features
***************************
If your machine is IBM PC or its compatibles, set environment variable
TERM with `ibmpc', then you can use cursor keys and functon
keys.
The functions which is assigned to those keys are as follows:
Key Function
----------+--------------------+-----------------
PgUp scroll-up Scroll text upward by page
PgDn scroll-down Scroll text downward by page
Insert set-mark-command Set mark current cursor position
Del delete-backward-char Delete previous character
UpArrow previous-line Move cursor vertically up
LeftArrow backward-char Move cursor left
RightArrow forward-char Move cursor right
DownArrow next-line Move cursor vertically down
Home beginning-of-buffer Move cursor beginning of buffer
End end-of-buffer Move cursor end of buffer
F1 help-for-help Show help for help
Shift-F1 describe-mode Show help of current mode
Ctrl-F1 describe-key Show help of key
F2 other-window Select different window
Shift-F2 switch-to-buffer Select buffer by name
Ctrl-F2 list-buffers Display a list of buffers
F3 delete-other-windows Make current window fill the screen
Shift-F3 delete-window Remove current window
Ctrl-F3 scroll-other-window Scroll text of other window upward by page
F4 split-window-vertically Split current window vertically
Shift-F4 enlarge-window Make current window bigger
Ctrl-F4 shrink-window Make current window smaller
F5 split-window-horizontally Split current window horizontally
Shift-F5 enlarge-window-horizontally Make current window wider
Ctrl-F5 shrink-window-horizontally Make current window narrower
F6 copy-region Copy from mark till cursor to yank-buffer
Shift-F6 kill-region Cut from mark till cursor to yank-buffer
Ctrl-F6 yank Paste yank-buffer to current cursor position
F7 goto-line Goto line
Shift-F7 isearch-forward Do incremental search forward
Ctrl-F7 query-replace Do query replace
F8 find-file Edit file
Shift-F8 save-buffer Save current buffer
Ctrl-F8 write-file Write current buffer into file
F9 dired 'Edit' directory
Shift-F9 compile Compile the program
Ctrl-F9 repeat-complex-command Edit and re-evaluate last command
F10 shell-command Execute command
Shift-F10 suspend-emacs Call DOS command interpreter
Ctrl-F10 save-buffers-kill-emacs Quit Emacs
Summary:
| F.1 | F.2 | F.3 | F.4 | F.5 | F.6 | F.7 | F.8 | F.9 | F.10 |
|help | nextW | delOW |splitWH |splitWV |copy | goto | read |dired |command |
s|mode |switchW| delW |largeWH |largeWV |kill |search | save | make |suspend |
c|key |buffers|scrlOW |shrnkWH |shrnkWV |yank |replace|write |repeat| quit |
If you want to append and/or change the function, use lisp variable
`term-setup-hook'. See `lisp/term/ibmpc.el'.
If you don't need cursor and function keys, append next line to
`$HOME/_emacs':
(setq term-file-prefix nil)
Differences from UNIX Version
*****************************
List of Functions which are not inplemented to Demacs
=====================================================
accept-process-output process-list
continue-process process-mark
delete-process process-name
file-locked-p process-send-eof
get-buffer-process process-send-region
get-process process-send-string
interrupt-process process-sentinel
kill-process process-status
list-processes processp
make-symbolic-link quit-process
open-network-stream set-process-buffer
process-buffer set-process-filter
process-command set-process-kanji-code
process-exit-status set-process-sentinel
process-filter start-process
process-id stop-process
process-kanji-code waiting-for-user-input-p
process-kill-without-query
List of Variables which are not inplemented to Demacs
=====================================================
delete-exited-processes process-connection-type
List of Functions added to Demacs
=================================
bdos intdos
define-file-name-file-type invoke-find-file-type
demacs-version make-register
disk-free-space register-value
disk-total-space set-cursor-mode
file-type-internal set-default-file-type
file-type-p set-file-type
find-file-not-found-set-file-type set-keyclick
find-file-type-from-file-name set-register-value
get-cursor-mode set-screen-mode
get-screen-mode toggle-pass8-mode
int86
List of Functions added to Demacs
=================================
default-file-type file-type
demacs-version file-type-alist
demacs-version-date find-file-type
dos-inhibit-setdisk pass8-mode
dos-machine-type register-name-by-byte-alist
file-name-file-type-alist register-name-by-word-alist