-(This assumes that Ghostscript is installed in the @file{"c:/gs"}
-directory.)
-
-@vindex dos-printer
-@vindex dos-ps-printer
- For backwards compatibility, the value of @code{dos-printer}
-(@code{dos-ps-printer}), if it has a value, overrides the value of
-@code{printer-name} (@code{ps-printer-name}), on MS-DOS and MS-Windows
-only.
-
-
-@node MS-DOS and MULE
-@section International Support on MS-DOS
-@cindex international support @r{(MS-DOS)}
-
- Emacs on MS-DOS supports the same international character sets as it
-does on GNU, Unix and other platforms (@pxref{International}), including
-coding systems for converting between the different character sets.
-However, due to incompatibilities between MS-DOS/MS-Windows and other systems,
-there are several DOS-specific aspects of this support that you should
-be aware of. This section describes these aspects.
-
-@table @kbd
-@item M-x dos-codepage-setup
-Set up Emacs display and coding systems as appropriate for the current
-DOS codepage.
-
-@item M-x codepage-setup
-Create a coding system for a certain DOS codepage.
-@end table
-
-@cindex codepage, MS-DOS
-@cindex DOS codepages
- MS-DOS is designed to support one character set of 256 characters at
-any given time, but gives you a variety of character sets to choose
-from. The alternative character sets are known as @dfn{DOS codepages}.
-Each codepage includes all 128 ASCII characters, but the other 128
-characters (codes 128 through 255) vary from one codepage to another.
-Each DOS codepage is identified by a 3-digit number, such as 850, 862,
-etc.
-
- In contrast to X, which lets you use several fonts at the same time,
-MS-DOS normally doesn't allow use of several codepages in a single
-session. MS-DOS was designed to load a single codepage at system
-startup, and require you to reboot in order to change
-it@footnote{Normally, one particular codepage is burnt into the display
-memory, while other codepages can be installed by modifying system
-configuration files, such as @file{CONFIG.SYS}, and rebooting. While
-third-party software is known to exist that allows to change the
-codepage without rebooting, we describe here how a stock MS-DOS system
-behaves.}. Much the same limitation applies when you run DOS
-executables on other systems such as MS-Windows.
-
-@cindex unibyte operation @r{(MS-DOS)}
- If you invoke Emacs on MS-DOS with the @samp{--unibyte} option
-(@pxref{Initial Options}), Emacs does not perform any conversion of
-non-ASCII characters. Instead, it reads and writes any non-ASCII
-characters verbatim, and sends their 8-bit codes to the display
-verbatim. Thus, unibyte Emacs on MS-DOS supports the current codepage,
-whatever it may be, but cannot even represent any other characters.
-
-@vindex dos-codepage
- For multibyte operation on MS-DOS, Emacs needs to know which
-characters the chosen DOS codepage can display. So it queries the
-system shortly after startup to get the chosen codepage number, and
-stores the number in the variable @code{dos-codepage}. Some systems
-return the default value 437 for the current codepage, even though the
-actual codepage is different. (This typically happens when you use the
-codepage built into the display hardware.) You can specify a different
-codepage for Emacs to use by setting the variable @code{dos-codepage} in
-your init file.
-
-@cindex language environment, automatic selection on @r{MS-DOS}
- Multibyte Emacs supports only certain DOS codepages: those which can
-display Far-Eastern scripts, like the Japanese codepage 932, and those
-that encode a single ISO 8859 character set.
-
- The Far-Eastern codepages can directly display one of the MULE
-character sets for these countries, so Emacs simply sets up to use the
-appropriate terminal coding system that is supported by the codepage.
-The special features described in the rest of this section mostly
-pertain to codepages that encode ISO 8859 character sets.
-
- For the codepages which correspond to one of the ISO character sets,
-Emacs knows the character set name based on the codepage number. Emacs
-automatically creates a coding system to support reading and writing
-files that use the current codepage, and uses this coding system by
-default. The name of this coding system is @code{cp@var{nnn}}, where
-@var{nnn} is the codepage number.@footnote{The standard Emacs coding
-systems for ISO 8859 are not quite right for the purpose, because
-typically the DOS codepage does not match the standard ISO character
-codes. For example, the letter @samp{@,{c}} (@samp{c} with cedilla) has
-code 231 in the standard Latin-1 character set, but the corresponding
-DOS codepage 850 uses code 135 for this glyph.}
-
-@cindex mode line @r{(MS-DOS)}
- All the @code{cp@var{nnn}} coding systems use the letter @samp{D} (for
-``DOS'') as their mode-line mnemonic. Since both the terminal coding
-system and the default coding system for file I/O are set to the proper
-@code{cp@var{nnn}} coding system at startup, it is normal for the mode
-line on MS-DOS to begin with @samp{-DD\-}. @xref{Mode Line}.
-Far-Eastern DOS terminals do not use the @code{cp@var{nnn}} coding
-systems, and thus their initial mode line looks like the Emacs default.
-
- Since the codepage number also indicates which script you are using,
-Emacs automatically runs @code{set-language-environment} to select the
-language environment for that script (@pxref{Language Environments}).
-
- If a buffer contains a character belonging to some other ISO 8859
-character set, not the one that the chosen DOS codepage supports, Emacs
-displays it using a sequence of ASCII characters. For example, if the
-current codepage doesn't have a glyph for the letter @samp{@`o} (small
-@samp{o} with a grave accent), it is displayed as @samp{@{`o@}}, where
-the braces serve as a visual indication that this is a single character.
-(This may look awkward for some non-Latin characters, such as those from
-Greek or Hebrew alphabets, but it is still readable by a person who
-knows the language.) Even though the character may occupy several
-columns on the screen, it is really still just a single character, and
-all Emacs commands treat it as one.
-
-@cindex IBM graphics characters (MS-DOS)
-@cindex box-drawing characters (MS-DOS)
-@cindex line-drawing characters (MS-DOS)
- Not all characters in DOS codepages correspond to ISO 8859
-characters---some are used for other purposes, such as box-drawing
-characters and other graphics. Emacs maps these characters to two
-special character sets called @code{eight-bit-control} and
-@code{eight-bit-graphic}, and displays them as their IBM glyphs.
-However, you should be aware that other systems might display these
-characters differently, so you should avoid them in text that might be
-copied to a different operating system, or even to another DOS machine
-that uses a different codepage.
-
-@vindex dos-unsupported-character-glyph
- Emacs supports many other characters sets aside from ISO 8859, but it
-cannot display them on MS-DOS. So if one of these multibyte characters
-appears in a buffer, Emacs on MS-DOS displays them as specified by the
-@code{dos-unsupported-character-glyph} variable; by default, this glyph
-is an empty triangle. Use the @kbd{C-u C-x =} command to display the
-actual code and character set of such characters. @xref{Position Info}.
-
-@findex codepage-setup
- By default, Emacs defines a coding system to support the current
-codepage. To define a coding system for some other codepage (e.g., to
-visit a file written on a DOS machine in another country), use the
-@kbd{M-x codepage-setup} command. It prompts for the 3-digit code of
-the codepage, with completion, then creates the coding system for the
-specified codepage. You can then use the new coding system to read and
-write files, but you must specify it explicitly for the file command
-when you want to use it (@pxref{Specify Coding}).
-
- These coding systems are also useful for visiting a file encoded using
-a DOS codepage, using Emacs running on some other operating system.
-
-@cindex MS-Windows codepages
- MS-Windows provides its own codepages, which are different from the
-DOS codepages for the same locale. For example, DOS codepage 850
-supports the same character set as Windows codepage 1252; DOS codepage
-855 supports the same character set as Windows codepage 1251, etc.
-The MS-Windows version of Emacs uses the current codepage for display
-when invoked with the @samp{-nw} option.
-
-@node MS-DOS Processes
-@section Subprocesses on MS-DOS
-
-@cindex compilation under MS-DOS
-@cindex inferior processes under MS-DOS
-@findex compile @r{(MS-DOS)}
-@findex grep @r{(MS-DOS)}
- Because MS-DOS is a single-process ``operating system,''
-asynchronous subprocesses are not available. In particular, Shell
-mode and its variants do not work. Most Emacs features that use
-asynchronous subprocesses also don't work on MS-DOS, including
-Shell mode and GUD. When in doubt, try and see; commands that
-don't work print an error message saying that asynchronous processes
-aren't supported.
-
- Compilation under Emacs with @kbd{M-x compile}, searching files with
-@kbd{M-x grep} and displaying differences between files with @kbd{M-x
-diff} do work, by running the inferior processes synchronously. This
-means you cannot do any more editing until the inferior process
-finishes.
-
- Spell checking also works, by means of special support for synchronous
-invocation of the @code{ispell} program. This is slower than the
-asynchronous invocation on other platforms
-
- Instead of the Shell mode, which doesn't work on MS-DOS, you can use
-the @kbd{M-x eshell} command. This invokes the Eshell package that
-implements a Posix-like shell entirely in Emacs Lisp.
-
- By contrast, Emacs compiled as native Windows application
-@strong{does} support asynchronous subprocesses. @xref{Windows
-Processes}.
-
-@cindex printing under MS-DOS
- Printing commands, such as @code{lpr-buffer} (@pxref{Hardcopy}) and
-@code{ps-print-buffer} (@pxref{PostScript}), work in MS-DOS by sending
-the output to one of the printer ports. @xref{MS-DOS Printing}.
-
- When you run a subprocess synchronously on MS-DOS, make sure the
-program terminates and does not try to read keyboard input. If the
-program does not terminate on its own, you will be unable to terminate
-it, because MS-DOS provides no general way to terminate a process.
-Pressing @kbd{C-c} or @kbd{C-@key{BREAK}} might sometimes help in these
-cases.
-
- Accessing files on other machines is not supported on MS-DOS. Other
-network-oriented commands such as sending mail, Web browsing, remote
-login, etc., don't work either, unless network access is built into
-MS-DOS with some network redirector.
-
-@cindex directory listing on MS-DOS
-@vindex dired-listing-switches @r{(MS-DOS)}
- Dired on MS-DOS uses the @code{ls-lisp} package where other
-platforms use the system @code{ls} command. Therefore, Dired on
-MS-DOS supports only some of the possible options you can mention in
-the @code{dired-listing-switches} variable. The options that work are
-@samp{-A}, @samp{-a}, @samp{-c}, @samp{-i}, @samp{-r}, @samp{-S},
-@samp{-s}, @samp{-t}, and @samp{-u}.
-
-@node Windows Processes
-@section Subprocesses on Windows 95 and NT
-
-Emacs compiled as a native Windows application (as opposed to the DOS
-version) includes full support for asynchronous subprocesses.
-In the Windows version, synchronous and asynchronous subprocesses work
-fine on both
-Windows 95 and Windows NT as long as you run only 32-bit Windows
-applications. However, when you run a DOS application in a subprocess,
-you may encounter problems or be unable to run the application at all;
-and if you run two DOS applications at the same time in two
-subprocesses, you may have to reboot your system.
-
-Since the standard command interpreter (and most command line utilities)
-on Windows 95 are DOS applications, these problems are significant when
-using that system. But there's nothing we can do about them; only
-Microsoft can fix them.
-
-If you run just one DOS application subprocess, the subprocess should
-work as expected as long as it is ``well-behaved'' and does not perform
-direct screen access or other unusual actions. If you have a CPU
-monitor application, your machine will appear to be 100% busy even when
-the DOS application is idle, but this is only an artifact of the way CPU
-monitors measure processor load.
-
-You must terminate the DOS application before you start any other DOS
-application in a different subprocess. Emacs is unable to interrupt or
-terminate a DOS subprocess. The only way you can terminate such a
-subprocess is by giving it a command that tells its program to exit.
-
-If you attempt to run two DOS applications at the same time in separate
-subprocesses, the second one that is started will be suspended until the
-first one finishes, even if either or both of them are asynchronous.
-
-If you can go to the first subprocess, and tell it to exit, the second
-subprocess should continue normally. However, if the second subprocess
-is synchronous, Emacs itself will be hung until the first subprocess
-finishes. If it will not finish without user input, then you have no
-choice but to reboot if you are running on Windows 95. If you are
-running on Windows NT, you can use a process viewer application to kill
-the appropriate instance of ntvdm instead (this will terminate both DOS
-subprocesses).
-
-If you have to reboot Windows 95 in this situation, do not use the
-@code{Shutdown} command on the @code{Start} menu; that usually hangs the
-system. Instead, type @kbd{CTL-ALT-@key{DEL}} and then choose
-@code{Shutdown}. That usually works, although it may take a few minutes
-to do its job.