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XEmacs / etc / MSDOS

XEmacs does not yet work under MSDOS.  If you would be interested in
porting XEmacs to MSDOS, please contact Chuck Thompson <cthomp@xemacs.org>.

The following information applies to FSF Emacs, not to XEmacs.

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This file describes use of Emacs 19 on MS-DOG.

* The commands `mode25' and `mode4350' change the number of 
lines of the screen.  You get 43 lines on an EGA monitor, 50 on
a VGA monitor.

* Ctrl-Break takes the place of C-g.  Using compilers prior to
djgpp 1.11 maint 5, you should not use Ctrl-Break unless you
run under DPMI (i.e., you are using Windows, Qdpmi, ...)

Actually, if Emacs is in an endless loop, you might as well go
ahead and try.  Usually it works, but sometimes Emacs crashes
with a stack trace.  This is not an Emacs bug.

* Character codes 0200-0237 are self-inserting.

* The keyboard support is made as X-like as possible.  This means
that events like M-S-f1 will be generated (by Shift + Alt + f1).

* Mouse support is partially implemented.

* The `compile' command works on MS-DOG, but it waits for the
compilation to finish before letting you edit again.  There's no other
way to do it, given the lack of asynchronous processes.

* The function `expand-file-name' maps upper case letters to lower
case letters, since MS-DOG does not distinguish.

* The new buffer-local variable `buffer-file-type' controls whether a
file contains text (newlines will be written as CR+LF) or binary data
(newlines written as LF).  Text is specified by nil, and binary by t.
The status of a buffer can be seen in the mode line as "T:" or "B:"
before the major mode.

Normally `buffer-file-type' is set automatically from the variable
`file-name-buffer-file-type-alist' which is an alist mapping regexps
to file types.

You can visit a file explicitly as text, or as binary, using the
commands `find-file-binary' and `find-file-text'.

* New variables `binary-process-input' and `binary-process-output'
control whether temporary files are opened as binary or as text
files.  nil means text, and t means binary.  The difference is
translation of CR+LF to LF and C-z handling.

* Environment variables "HOME", "EMACSPATH", "TERM", "SHELL",
"USER", "NAME", and "TZ" are given default values as suitable
for a single user system.  See src/msdos.c for details.

* The function `substitute-in-file-name' disregards case in
environment variables, as the MS-DOG SET command does.

* The variable `msdos-shells' contains a list of commands that
are shells.  This variable is used to convert to map Unix-like
commands like "$SHELL -c /some/command" to MS-DOG commands
like "$SHELL /c \some\command".