1 GNU Emacs Installation Guide
2 Copyright (c) 1992, 1994, 1996, 1997 Free software Foundation, Inc.
4 Permission is granted to anyone to make or distribute verbatim copies
5 of this document as received, in any medium, provided that the
6 copyright notice and permission notice are preserved,
7 and that the distributor grants the recipient permission
8 for further redistribution as permitted by this notice.
10 Permission is granted to distribute modified versions
11 of this document, or of portions of it,
12 under the above conditions, provided also that they
13 carry prominent notices stating who last changed them,
14 and that any new or changed statements about the activities
15 of the Free Software Foundation are approved by the Foundation.
18 ADDITIONAL DISTRIBUTION FILES
22 The Emacs Lisp code for input methods for various international
23 character scripts is distributed in a separate tar file because of its
24 large size. This file is called leim-M.N.tar.gz, with the same
25 version number as Emacs, and it unpacks into the directory
26 emacs-M.N/leim. Thus, if you unpack it in the same directory where
27 you unpacked the Emacs distribution, it fills in a subdirectory
28 of the Emacs distribution.
30 If you have already unpacked the Leim tar file into a subdirectory of
31 the Emacs sources, building and installing Emacs automatically
32 installs the input method support as well. If you unpack the Leim tar
33 file into the Emacs sources after building and installing Emacs, just
34 build Emacs again and install it again.
36 * intlfonts-VERSION.tar.gz
38 The intlfonts distribution contains X11 fonts that Emacs needs in
39 order to display international characters. If you see a non-ASCII
40 character appear as a hollow box, that means you don't have a font for
41 it. You might find a font in the intlfonts distribution. If some
42 characters don't look right, or appear improperly aligned, a font
43 from the intlfonts distribution might look better.
45 The intlfonts distribution contains its own installation instructions,
46 in the intlfonts/README file.
49 BUILDING AND INSTALLATION:
51 (This is for a Unix or Unix-like system. For MSDOS, see below; search
52 for MSDOG. For Windows NT or Windows 95, see the file nt/INSTALL.)
54 1) Make sure your system has enough swapping space allocated to handle
55 a program whose pure code is 900k bytes and whose data area is at
56 least 400k and can reach 8Mb or more. If the swapping space is
57 insufficient, you will get an error in the command `temacs -batch -l
58 loadup dump', found in `./src/Makefile.in', or possibly when
59 running the final dumped Emacs.
61 Building Emacs requires about 70 Mb of disk space (including the Emacs
62 sources). Once installed, Emacs occupies about 35 Mb in the file
63 system where it is installed; this includes the executable files, Lisp
64 libraries, miscellaneous data files, and on-line documentation. If
65 the building and installation take place in different directories,
66 then the installation procedure momentarily requires 70+35 Mb.
68 2) Consult `./etc/MACHINES' to see what configuration name you should
69 give to the `configure' program. That file offers hints for
70 getting around some possible installation problems.
72 3) You can build Emacs in the top-level Emacs source directory
73 or in a separate directory.
75 3a) To build in the top-level Emacs source directory, go to that
76 directory and run the program `configure' as follows:
78 ./configure [CONFIGURATION-NAME] [--OPTION[=VALUE]] ...
80 The CONFIGURATION-NAME argument should be a configuration name given
81 in `./etc/MACHINES', with the system version number added at the end.
83 You should try first omitting CONFIGURATION-NAME. This way,
84 `configure' will try to guess your system type. If it cannot guess,
85 or if something goes wrong in building or installing Emacs this way,
86 try again specifying the proper CONFIGURATION-NAME explicitly.
88 If you don't want X support, specify `--with-x=no'. If you omit this
89 option, `configure' will try to figure out for itself whether your
90 system has X, and arrange to use it if present.
92 The `--x-includes=DIR' and `--x-libraries=DIR' options tell the build
93 process where the compiler should look for the include files and
94 object libraries used with the X Window System. Normally, `configure'
95 is able to find them; these options are necessary if you have your X
96 Window System files installed in unusual places. These options also
97 accept a list of directories, separated with colons.
99 To get more attractive menus, you can specify an X toolkit when you
100 configure Emacs; use the option `--with-x-toolkit=TOOLKIT', where
101 TOOLKIT is `athena' or `motif' (`yes' and `lucid' are synonyms for
102 `athena'). On some systems, it does not work to use a toolkit with
105 The `--with-gcc' option specifies that the build process should
106 compile Emacs using GCC. If you don't want to use GCC, specify
107 `--with-gcc=no'. If you omit this option, `configure' will search
108 for GCC in your path, and use it if present.
110 If you want the Emacs mail reader RMAIL to read mail from a POP
111 server, you must specify `--with-pop'. This provides support for the
112 POP3 protocol; older versions are not supported. For
113 Kerberos-authenticated POP add `--with-kerberos', for Hesiod support
114 add `--with-hesiod'. These options enable Emacs to use POP; whether
115 Emacs uses POP is controlled by individual users--see the Rmail
116 chapter of the Emacs manual.
118 The `--prefix=PREFIXDIR' option specifies where the installation process
119 should put emacs and its data files. This defaults to `/usr/local'.
120 - Emacs (and the other utilities users run) go in PREFIXDIR/bin
121 (unless the `--exec-prefix' option says otherwise).
122 - The architecture-independent files go in PREFIXDIR/share/emacs/VERSION
123 (where VERSION is the version number of Emacs, like `19.27').
124 - The architecture-dependent files go in
125 PREFIXDIR/libexec/emacs/VERSION/CONFIGURATION
126 (where CONFIGURATION is the configuration name, like mips-dec-ultrix4.2),
127 unless the `--exec-prefix' option says otherwise.
129 The `--exec-prefix=EXECDIR' option allows you to specify a separate
130 portion of the directory tree for installing architecture-specific
131 files, like executables and utility programs. If specified,
132 - Emacs (and the other utilities users run) go in EXECDIR/bin, and
133 - The architecture-dependent files go in
134 EXECDIR/libexec/emacs/VERSION/CONFIGURATION.
135 EXECDIR/bin should be a directory that is normally in users' PATHs.
137 For example, the command
139 ./configure mips-dec-ultrix --with-x11
141 configures Emacs to build for a DECstation running Ultrix, with
142 support for the X11 window system.
144 `configure' doesn't do any compilation or installation
145 itself. It just creates the files that influence those things:
146 `./Makefile', `lib-src/Makefile', `oldXMenu/Makefile',
147 `lwlib/Makefile', `src/Makefile', and `./src/config.h'. For details
148 on exactly what it does, see the section called `CONFIGURATION BY
151 When it is done, `configure' prints a description of what it did and
152 creates a shell script `config.status' which, when run, recreates the
153 same configuration. If `configure' exits with an error after
154 disturbing the status quo, it removes `config.status'. `configure'
155 also creates a file `config.cache' that saves the results of its tests
156 to make reconfiguring faster, and a file `config.log' containing compiler
157 output (useful mainly for debugging `configure'). You can give
158 `configure' the option `--cache-file=FILE' to use the results of the
159 tests in FILE instead of `config.cache'. Set FILE to `/dev/null' to
160 disable caching, for debugging `configure'.
162 The work of `configure' can be done by editing various files in the
163 distribution, but using `configure' is easier. See the section called
164 "CONFIGURATION BY HAND" below if you want to do the configuration
167 3b) To build in a separate directory, go to that directory
168 and run the program `configure' as follows:
170 SOURCE-DIR/configure CONFIGURATION-NAME [--OPTION[=VALUE]] ...
172 SOURCE-DIR refers to the top-level Emacs source directory which is
173 where Emacs's configure script is located. `configure' looks for the
174 Emacs source code in the directory that `configure' is in.
176 To build in a separate directory, you must use a version of `make'
177 that supports the `VPATH' variable, such as GNU `make'.
179 3c) Some people try to build in a separate directory by filling
180 it full of symlinks to the files in the real source directory.
181 If you do that, `make all' does work, but `make install' fails:
182 it copies the symbolic links rather than the actual files.
184 As far as is known, there is no particular reason to use
185 a directory full of links rather than use the standard GNU
186 facilities to build in a separate directory (see 3b above).
188 4) Look at `./lisp/paths.el'; if some of those values are not right
189 for your system, set up the file `./lisp/site-init.el' with Emacs
190 Lisp code to override them; it is not a good idea to edit paths.el
191 itself. YOU MUST USE THE LISP FUNCTION `setq' TO ASSIGN VALUES,
192 rather than `defvar', as used by `./lisp/paths.el'. For example,
194 (setq news-inews-program "/usr/bin/inews")
196 is how you would override the default value of the variable
197 news-inews-program (which is "/usr/local/inews").
199 Before you override a variable this way, *look at the value* that the
200 variable gets by default! Make sure you know what kind of value the
201 variable should have. If you don't pay attention to what you are
202 doing, you'll make a mistake.
204 5) Put into `./lisp/site-init.el' or `./lisp/site-load.el' any Emacs
205 Lisp code you want Emacs to load before it is dumped out. Use
206 site-load.el for additional libraries if you arrange for their
207 documentation strings to be in the etc/DOC file (see
208 src/Makefile.in if you wish to figure out how to do that). For all
209 else, use site-init.el. Do not load byte-compiled code which
210 was build with a non-nil value of `byte-compile-dynamic'.
212 If you set load-path to a different value in site-init.el or
213 site-load.el, Emacs will use *precisely* that value when it starts up
214 again. If you do this, you are on your own!
216 Note that, on some systems, the code you place in site-init.el must
217 not use expand-file-name or any other function which may look
218 something up in the system's password and user information database.
219 See `./etc/PROBLEMS' for more details on which systems this affects.
221 The `site-*.el' files are nonexistent in the distribution. You do not
222 need to create them if you have nothing to put in them.
224 6) Refer to the file `./etc/TERMS' for information on fields you may
225 wish to add to various termcap entries. The files `./etc/termcap.ucb'
226 and `./etc/termcap.dat' may already contain appropriately-modified
229 7) Run `make' in the top directory of the Emacs distribution to finish
230 building Emacs in the standard way. The final executable file is
231 named `src/emacs'. You can execute this file "in place" without
232 copying it, if you wish; then it automatically uses the sibling
233 directories ../lisp, ../lib-src, ../info.
235 Or you can "install" the executable and the other Emacs into their
236 installed locations, with `make install'. By default, Emacs's files
237 are installed in the following directories:
239 `/usr/local/bin' holds the executable programs users normally run -
240 `emacs', `etags', `ctags', `b2m', `emacsclient',
243 `/usr/local/share/emacs/VERSION/lisp' holds the Emacs Lisp library;
244 `VERSION' stands for the number of the Emacs version
245 you are installing, like `18.59' or `19.27'. Since the
246 Lisp library changes from one version of Emacs to
247 another, including the version number in the path
248 allows you to have several versions of Emacs installed
249 at the same time; in particular, you don't have to
250 make Emacs unavailable while installing a new version.
252 `/usr/local/share/emacs/VERSION/site-lisp' holds the local Emacs Lisp
253 files installed for Emacs version VERSION only.
255 `/usr/local/share/emacs/site-lisp' holds the local Emacs Lisp
256 files installed for all Emacs versions.
258 When Emacs is installed, it searches for its Lisp files
259 in `/usr/local/share/emacs/VERSION/site-lisp', then in
260 `/usr/local/share/emacs/site-lisp', and finally in
261 `/usr/local/share/emacs/VERSION/lisp'.
263 `/usr/local/share/emacs/VERSION/etc' holds the Emacs tutorial, the DOC
264 file, the `yow' database, and other
265 architecture-independent files Emacs might need while
266 running. VERSION is as specified for `.../lisp'.
268 `/usr/local/libexec/emacs/VERSION/CONFIGURATION-NAME' contains executable
269 programs used by Emacs that users are not expected to
271 `VERSION' is the number of the Emacs version you are
272 installing, and `CONFIGURATION-NAME' is the argument
273 you gave to the `configure' program to identify the
274 architecture and operating system of your machine,
275 like `mips-dec-ultrix' or `sparc-sun-sunos'. Since
276 these files are specific to the version of Emacs,
277 operating system, and architecture in use, including
278 the configuration name in the path allows you to have
279 several versions of Emacs for any mix of machines and
280 operating systems installed at the same time; this is
281 useful for sites at which different kinds of machines
282 share the file system Emacs is installed on.
284 `/usr/local/info' holds the on-line documentation for Emacs, known as
285 "info files". Many other GNU programs are documented
286 using info files as well, so this directory stands
287 apart from the other, Emacs-specific directories.
289 `/usr/local/man/man1' holds the man pages for the programs installed
292 If these directories are not what you want, you can specify where to
293 install Emacs's libraries and data files or where Emacs should search
294 for its Lisp files by giving values for `make' variables as part of
295 the command. See the section below called `MAKE VARIABLES' for more
298 8) Check the file `dir' in your site's info directory (usually
299 /usr/local/info) to make sure that it has a menu entry for the Emacs
302 9) If your system uses lock files to interlock access to mailer inbox files,
303 then you might need to make the movemail program setuid or setgid
304 to enable it to write the lock files. We believe this is safe.
306 10) You are done! You can remove executables and object files from
307 the build directory by typing `make clean'. To also remove the files
308 that `configure' created (so you can compile Emacs for a different
309 configuration), type `make distclean'.
315 You can change where the build process installs Emacs and its data
316 files by specifying values for `make' variables as part of the `make'
317 command line. For example, if you type
319 make install bindir=/usr/local/gnubin
321 the `bindir=/usr/local/gnubin' argument indicates that the Emacs
322 executable files should go in `/usr/local/gnubin', not
325 Here is a complete list of the variables you may want to set.
327 `bindir' indicates where to put executable programs that users can
328 run. This defaults to /usr/local/bin.
330 `datadir' indicates where to put the architecture-independent
331 read-only data files that Emacs refers to while it runs; it
332 defaults to /usr/local/share. We create the following
333 subdirectories under `datadir':
334 - `emacs/VERSION/lisp', containing the Emacs Lisp library, and
335 - `emacs/VERSION/etc', containing the Emacs tutorial, the DOC
336 file, and the `yow' database.
337 `VERSION' is the number of the Emacs version you are installing,
338 like `18.59' or `19.0'. Since these files vary from one version
339 of Emacs to another, including the version number in the path
340 allows you to have several versions of Emacs installed at the
341 same time; this means that you don't have to make Emacs
342 unavailable while installing a new version.
344 `libexecdir' indicates where to put architecture-specific data files that
345 Emacs refers to as it runs; it defaults to `/usr/local/libexec'.
346 We create the following subdirectories under `libexecdir':
347 - `emacs/VERSION/CONFIGURATION-NAME', containing executable
348 programs used by Emacs that users are not expected to run
350 `VERSION' is the number of the Emacs version you are installing,
351 and `CONFIGURATION-NAME' is the argument you gave to the
352 `configure' program to identify the architecture and operating
353 system of your machine, like `mips-dec-ultrix' or
354 `sparc-sun-sunos'. Since these files are specific to the version
355 of Emacs, operating system, and architecture in use, including
356 the configuration name in the path allows you to have several
357 versions of Emacs for any mix of machines and operating systems
358 installed at the same time; this is useful for sites at which
359 different kinds of machines share the file system Emacs is
362 `infodir' indicates where to put the info files distributed with
363 Emacs; it defaults to `/usr/local/info'.
365 `mandir' indicates where to put the man pages for Emacs and its
366 utilities (like `etags'); it defaults to
367 `/usr/local/man/man1'.
369 `manext' gives the extension the man pages should be installed with.
370 It should contain a period, followed by the appropriate
371 digit. It defaults to `.1'. For example given the default
372 values for `mandir' and `manext', the Emacs man page would be
373 installed as `/usr/local/man/man1/emacs.1'.
375 `prefix' doesn't give a path for any specific part of Emacs; instead,
376 its value is used to determine the defaults for all the
377 architecture-independent path variables - `datadir',
378 `sharedstatedir', `infodir', and `mandir'. Its default value is
379 `/usr/local'; the other variables add on `lib' or `man' to it
382 For example, suppose your site generally places GNU software
383 under `/usr/users/software/gnusoft' instead of `/usr/local'.
385 `prefix=/usr/users/software/gnusoft'
386 in the arguments to `make', you can instruct the build process
387 to place all of the Emacs data files in the appropriate
388 directories under that path.
390 `exec_prefix' serves the same purpose as `prefix', but instead
391 determines the default values for the architecture-dependent
392 path variables - `bindir' and `libexecdir'.
394 The above variables serve analogous purposes in the makefiles for all
395 GNU software; this variable is specific to Emacs.
397 `archlibdir' indicates where Emacs installs and expects the executable
398 files and other architecture-dependent data it uses while
399 running. Its default value, based on `libexecdir' (which
400 see), is `/usr/local/libexec/emacs/VERSION/CONFIGURATION-NAME'
401 (where VERSION and CONFIGURATION-NAME are as described above).
403 Remember that you must specify any variable values you need each time
404 you run `make' in the top directory. If you run `make' once to build
405 emacs, test it, and then run `make' again to install the files, you
406 must provide the same variable settings each time. To make the
407 settings persist, you can edit them into the `Makefile' in the top
408 directory, but be aware that running the `configure' program erases
409 `Makefile' and rebuilds it from `Makefile.in'.
411 The path for finding Lisp files is specified in src/paths.h,
412 a file which is generated by running configure. To change the path,
413 you can edit the definition of PATH_LOADSEARCH in that file
414 before you run `make'.
416 The top-level Makefile stores the variable settings it used in the
417 Makefiles for the subdirectories, so you don't have to specify them
418 when running make in the subdirectories.
421 CONFIGURATION BY HAND
423 Instead of running the `configure' program, you have to perform the
426 1) Copy `./src/config.in' to `./src/config.h'.
428 2) Consult `./etc/MACHINES' to see what configuration name you should
429 use for your system. Look at the code of the `configure' script to
430 see which operating system and architecture description files from
431 `src/s' and `src/m' should be used for that configuration name. Edit
432 `src/config.h', and change the two `#include' directives to include
433 the appropriate system and architecture description files.
435 2) Edit `./src/config.h' to set the right options for your system. If
436 you need to override any of the definitions in the s/*.h and m/*.h
437 files for your system and machine, do so by editing config.h, not by
438 changing the s/*.h and m/*.h files. Occasionally you may need to
439 redefine parameters used in `./lib-src/movemail.c'.
441 3) Create src/Makefile and lib-src/Makefile from the corresponding
442 `Makefile.in' files. First copy `Makefile.in' to `Makefile.c',
443 then edit in appropriate substitutions for the @...@ constructs,
444 and then copy the shell commands near the end of `configure'
445 that run cpp to construct `Makefile'.
447 4) Create `Makefile' files in various other directories
448 from the corresponding `Makefile.in' files. This isn't so hard,
449 just a matter of substitution.
451 The `configure' script is built from `configure.in' by the `autoconf'
452 program. You need version 2.0 or newer of `autoconf' to rebuild `configure'.
454 BUILDING GNU EMACS BY HAND
456 Once Emacs is configured, running `make' in the top directory performs
459 1) Run `make src/paths.h' in the top directory. This produces
460 `./src/paths.h' from the template file `./src/paths.in', changing
461 the paths to the values specified in `./Makefile'.
463 2) Go to directory `./lib-src' and run `make'. This creates
464 executables named `ctags' and `etags' and `wakeup' and `make-docfile'
465 and `digest-doc' and `test-distrib'. And others.
467 3) Go to directory `./src' and Run `make'. This refers to files in
468 the `./lisp' and `./lib-src' subdirectories using names `../lisp' and
471 This creates a file `./src/emacs' which is the runnable Emacs,
472 which has another name that contains a version number.
473 Each time you do this, that version number increments in the last place.
475 It also creates a file in `./etc' whose name is `DOC' followed by the
476 current Emacs version. This file contains documentation strings for
477 all the functions in Emacs. Each time you run make to make a new
478 emacs, a new DOC file with a new name is made. You must keep the DOC
479 file for an Emacs version as long as you keep using that Emacs
485 The steps below are done by running `make install' in the main
486 directory of the Emacs distribution.
488 1) Copy `./lisp' and its subdirectories, `./etc', and the executables
489 in `./lib-src' to their final destinations, as selected in `./src/paths.h'.
491 Strictly speaking, not all of the executables in `./lib-src' need be copied.
492 - The programs `cvtmail', `emacsserver', `fakemail', `hexl',
493 `movemail', `profile', `rcs2log', `timer', `vcdiff', `wakeup',
494 and `yow' are used by Emacs; they do need to be copied.
495 - The programs `etags', `ctags', `emacsclient', `b2m', and `rcs-checkin'
496 are intended to be run by users; they are handled below.
497 - The programs `make-docfile' and `test-distrib' were
498 used in building Emacs, and are not needed any more.
499 - The programs `digest-doc' and `sorted-doc' convert a `DOC' file into
500 a file for users to read. There is no important reason to move them.
502 2) Copy the files in `./info' to the place specified in
503 `./lisp/site-init.el' or `./lisp/paths.el'. Note that if the
504 destination directory already contains a file named `dir', you
505 probably don't want to replace it with the `dir' file in the Emacs
506 distribution. Instead, you should make sure that the existing `dir'
507 file contains an appropriate menu entry for the Emacs info.
509 3) Copy `./src/emacs' to `/usr/local/bin', or to some other directory
510 in users' search paths. `./src/emacs' has an alternate name
511 `./src/emacs-EMACSVERSION'; you may wish to make a symbolic link named
512 `/usr/local/bin/emacs' pointing to that alternate name, as an easy way
513 of installing different versions.
515 You can delete `./src/temacs'.
517 4) Copy the programs `b2m', `emacsclient', `ctags', `etags', and
518 `rcs-checkin' from `./lib-src' to `/usr/local/bin'. These programs are
519 intended for users to run.
521 5) Copy the man pages in `./etc' for emacs, ctags, and etags into the
522 appropriate man directories.
524 6) The files in the `./src' subdirectory, except for `emacs', are not
525 used by Emacs once it is built. However, it is very desirable to keep
526 the source on line for debugging.
531 See the file PROBLEMS in etc subdirectory for a list of various
532 problems sometimes encountered, and what to do about them.
535 Installation on MSDOG (a.k.a. MSDOS)
537 To install on MSDOG, you need to have the GNU C compiler for MSDOG
538 (also known as djgpp), GNU Make, rm, mv, and sed. See the remarks in
539 config.bat for more information about locations and versions. The
540 file etc/FAQ includes pointers to Internet sites where you can find
541 the necessary utilities; search for "MS-DOS". The configuration step
542 (see below) will test for these utilities and will refuse to continue
543 if any of them isn't found.
545 If you are building the MSDOG version of Emacs on an MSDOG-like system
546 which supports long file names (e.g. Windows 95), you need to make
547 sure that long file names are handled consistently both when you
548 unpack the distribution and compile it. If you intend to compile with
549 DJGPP v2.0 or later, and long file names support is enabled (LFN=y in
550 the environment), you need to unpack Emacs distribution in a way that
551 doesn't truncate the original long filenames to the DOS 8.3 namespace;
552 the easiest way to do this is to use djtar program which comes with
553 DJGPP, since it will note the LFN setting and behave accordingly.
554 DJGPP v1 doesn't support long filenames, so you must unpack Emacs with
555 a program that truncates the filenames to 8.3 naming as it extracts
556 files; again, using djtar after setting LFN=n is the recommended way.
557 You can build Emacs with LFN=n even if you use DJGPP v2, if some of
558 your tools don't support long file names: just ensure that LFN is set
559 to `n' during both unpacking and compiling.
561 (By the time you read this, you have already unpacked the Emacs
562 distribution, but if the explanations above imply that you should have
563 done it differently, it's safer to delete the directory tree created
564 by the unpacking program and unpack Emacs again, than to risk running
565 into problems during the build process.)
567 It is important to understand that the runtime support of long file
568 names by the Emacs binary is NOT affected by the LFN setting during
569 compilation; Emacs compiled with DJGPP v2.0 or later will always
570 support long file names on Windows 95 no matter what was the setting
571 of LFN at compile time. However, if you compiled with LFN disabled
572 and want to enable LFN support after Emacs was already built, you need
573 to make sure that the support files in the lisp, etc and info
574 directories are called by their original long names as found in the
575 distribution. You can do this either by renaming the files manually,
576 or by extracting them from the original distribution archive with
577 djtar after you set LFN=y in the environment.
579 To unpack Emacs with djtar, type this command:
583 (This assumes that the Emacs distribution is called `emacs.tgz' on
586 When unpacking is done, a directory called `emacs-XX.YY' will be
587 created, where XX.YY is the Emacs version. To build and install
588 Emacs, chdir to that directory and type these commands:
593 Building Emacs creates executable files in the src and lib-src
594 directories. Installing Emacs on MSDOS moves these executables to a
595 sibling directory called bin. For example, if you build in directory
596 /emacs, installing moves the executables from /emacs/src and
597 /emacs/lib-src to the directory /emacs/bin, so you can then delete the
598 subdirectories /emacs/src and /emacs/lib-src if you wish. The only
599 subdirectories you need to keep are bin, lisp, etc and info. The bin
600 subdirectory should be added to your PATH. The msdos subdirectory
601 includes a PIF and an icon file for Emacs which you might find useful
602 if you run Emacs under MS Windows.
604 Emacs on MSDOS finds the lisp, etc and info directories by looking in
605 ../lisp, ../etc and ../info, starting from the directory where the
606 Emacs executable was run from. You can override this by setting the
607 environment variables EMACSDATA (for the location of `etc' directory),
608 EMACSLOADPATH (for the location of `lisp' directory) and INFOPATH (for
609 the location of the `info' directory).
611 MSDOG is a not a multitasking operating system, so Emacs features such
612 as asynchronous subprocesses that depend on multitasking will not
613 work. Synchronous subprocesses do work.
615 Version 2.0 of djgpp has two bugs that affect Emacs. We've included
616 corrected versions of two files from djgpp in the msdos subdirectory:
617 is_exec.c and sigaction.c. To work around the bugs, compile these
618 files and link them into temacs. Djgpp version 2.01 have these bugs
619 fixed, so upgrade if you can before building Emacs.