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[bpt/emacs.git] / INSTALL

GNU Emacs Installation Guide
Copyright (c) 1992, 1994 Free software Foundation, Inc.

   Permission is granted to anyone to make or distribute verbatim copies
   of this document as received, in any medium, provided that the
   copyright notice and permission notice are preserved,
   and that the distributor grants the recipient permission
   for further redistribution as permitted by this notice.

   Permission is granted to distribute modified versions
   of this document, or of portions of it,
   under the above conditions, provided also that they
   carry prominent notices stating who last changed them,
   and that any new or changed statements about the activities
   of the Free Software Foundation are approved by the Foundation.


BUILDING AND INSTALLATION:
(This is for a Unix or Unix-like system.  For MSDOS, see below;
search for MSDOG.)

1) Make sure your system has enough swapping space allocated to handle
a program whose pure code is 900k bytes and whose data area is at
least 400k and can reach 8Mb or more.  If the swapping space is
insufficient, you will get an error in the command `temacs -batch -l
loadup dump', found in `./src/Makefile.in.in', or possibly when
running the final dumped Emacs.
 
Building Emacs requires about 50 Mb of disk space (including the Emacs
sources).  Once installed, Emacs occupies about 20 Mb in the file
system where it is installed; this includes the executable files, Lisp
libraries, miscellaneous data files, and on-line documentation.  If
the building and installation take place in different directories,
then the installation procedure momentarily requires 50+20 Mb.

2) Consult `./etc/MACHINES' to see what configuration name you should
give to the `configure' program.  That file sometimes offers hints for
getting around some possible installation problems.

3) In the top directory of the Emacs distribution, run the program
`configure' as follows:

    ./configure CONFIGURATION-NAME [--OPTION[=VALUE]] ...

The CONFIGURATION-NAME argument should be a configuration name given
in `./etc/MACHINES'.  If omitted, `configure' will try to guess your
system type by inspecting its environment; if it cannot, you must find
the appropriate configuration name in `./etc/MACHINES' and specify it
explicitly.

The `--with-x', `--with-x11', and `--with-x10' options specify which
window system Emacs should support.  If you don't want X support,
specify `--with-x=no'.  If all of these options are omitted,
`configure' will try to figure out for itself whether your system has
X11, and arrange to use it if present.

The `--x-includes=DIR' and `--x-libraries=DIR' options tell the build
process where the compiler should look for the include files and
object libraries used with the X Window System.  Normally, your
compiler should be able to find these by default; these options should
only be necessary if you have your X Window System files installed in
unusual places.

You can specify toolkit operation when you configure Emacs; use the
option --with-x-toolkit.

Note: on some systems, it does not work to use the toolkit with shared
libraries.

The `--run-in-place' option sets up default values for the path
variables in `./Makefile' so that Emacs will expect to find its data
files (lisp libraries, runnable programs, and the like) in the same
locations they occupy while Emacs builds.  This means that you don't
have to install Emacs in order to run it; it uses its data files as
they were unpacked.

The `--with-gcc' option specifies that the build process should
compile Emacs using GCC.  If you don't want to use GCC, specify
`--with-gcc=no'.  If this option is omitted, `configure' will search
for GCC in your load path, and use it if present.

The `--srcdir=DIR' option specifies that the configuration and build
processes should look for the Emacs source code in DIR, when DIR is
not the current directory.

You can use `--srcdir' to build Emacs for several different machine
types from a single source directory.  Make separate build directories
for the different configuration types, and in each one, build Emacs
specifying the common source directory with `--srcdir'.

The `--prefix=PREFIXDIR' option specifies where the installation process
should put emacs and its data files.  This defaults to `/usr/local'.
- Emacs (and the other utilities users run) go in PREFIXDIR/bin
  (unless the `--exec-prefix' option says otherwise).
- The architecture-independent files go in PREFIXDIR/lib/emacs/VERSION
  (where VERSION is the version number of Emacs, like `19.7').
- The architecture-dependent files go in
  PREFIXDIR/lib/emacs/VERSION/CONFIGURATION
  (where CONFIGURATION is the configuration name, like mips-dec-ultrix4.2),
  unless the `--exec-prefix' option says otherwise.

The `--exec-prefix=EXECDIR' option allows you to specify a separate
portion of the directory tree for installing architecture-specific
files, like executables and utility programs.  If specified,
- Emacs (and the other utilities users run) go in EXECDIR/bin, and
- The architecture-dependent files go in
  EXECDIR/lib/emacs/VERSION/CONFIGURATION.
EXECDIR/bin should be a directory that is normally in users' PATHs.

For example, the command

    ./configure mips-dec-ultrix --with-x11

configures Emacs to build for a DECstation running Ultrix, with
support for the X11 window system.

The `configure' program does not accept abbreviations for its
options.

Note that `configure' doesn't do any compilation or installation
itself.  It just creates the files that influence those things:
`./Makefile', `build-install', and `./src/config.h'.  For details on
exactly what it does, see the section called `CONFIGURATION BY HAND',
below.

When it is done, `configure' prints a description of what it did and
leaves a copy in the file `config.status'.  That file is also a shell
script which, when run, recreates the same configuration; it contains
the verbal description as a comment.  If `configure' exits with an
error after disturbing the status quo, it removes `config.status'.

The work of `configure' can be done by editing various files in the
distribution, but using `configure' is supposed to be simpler.  See
the section called "CONFIGURATION BY HAND" below if you want to do the
configuration yourself.

4) Look at `./lisp/paths.el'; if some of those values are not right
for your system, edit the file `./lisp/site-init.el' containing Emacs
Lisp code to override them; you probably don't want to edit paths.el
itself.  YOU MUST USE THE LISP FUNCTION `setq' TO ASSIGN VALUES,
rather than `defvar', as used by `./lisp/paths.el'.  For example,

     (setq news-inews-program "/usr/bin/inews")

is how you would override the default value of the variable
news-inews-program (which is "/usr/local/inews").

Note that, on some systems, the code you place in site-init.el must
not use expand-file-name or any other function which may look
something up in the system's password and user information database.
See `./PROBLEMS' for more details on which systems this affects.

5) Put into `./lisp/site-init.el' or `./lisp/site-load.el' any Emacs
Lisp code you want Emacs to load before it is dumped out.  Use
site-load.el for additional libraries if you arrange for their
documentation strings to be in the etc/DOC file (see
src/Makefile.in.in if you wish to figure out how to do that).  For all
else, use site-init.el.

Note that, on some systems, the code you place in site-init.el must
not use expand-file-name or any other function which may look
something up in the system's password and user information database.
See `./PROBLEMS' for more details on which systems this affects.

The `site-*.el' files are nonexistent in the distribution.  You do not
need to create them if you have nothing to put in them.

6) Refer to the file `./etc/TERMS' for information on fields you may
wish to add to various termcap entries.  The files `./etc/termcap.ucb'
and `./etc/termcap.dat' may already contain appropriately-modified
entries.

7) Run `make' in the top directory of the Emacs distribution to finish
building Emacs in the standard way.  The final executable file will be
named `src/emacs'.  If you want to have Emacs's executable programs
and data files installed as well, run `make install'.

By default, Emacs installs its files in the following directories:

`/usr/local/bin' holds the executable programs users normally run -
                `emacs', `etags', `ctags', `b2m', and `emacsclient'.

`/usr/local/lib/emacs/VERSION/lisp' holds the Emacs Lisp library;
                `VERSION' stands for the number of the Emacs version
                you are installing, like `18.59' or `19.0'.  Since the
                lisp library changes from one version of Emacs to
                another, including the version number in the path
                allows you to have several versions of Emacs installed
                at the same time; this means that you don't have to
                make Emacs unavailable while installing a new
                version.

                Emacs searches for its lisp files in
                `/usr/local/lib/emacs/site-lisp', then in this
                directory.

`/usr/local/lib/emacs/VERSION/etc' holds the Emacs tutorial, the DOC
                file, the `yow' database, and other
                architecture-independent files Emacs might need while
                running.  VERSION is as specified for `.../lisp'.

`/usr/local/lib/emacs/lock' contains files indicating who is editing
                what, so Emacs can detect editing clashes between
                users.

`/usr/local/lib/emacs/VERSION/CONFIGURATION-NAME' contains executable
                programs used by Emacs that users are not expected to
                run themselves.
                `VERSION' is the number of the Emacs version you are
                installing, and `CONFIGURATION-NAME' is the argument
                you gave to the `configure' program to identify the
                architecture and operating system of your machine,
                like `mips-dec-ultrix' or `sparc-sun-sunos'.  Since
                these files are specific to the version of Emacs,
                operating system, and architecture in use, including
                the configuration name in the path allows you to have
                several versions of Emacs for any mix of machines and
                operating systems installed at the same time; this is
                useful for sites at which different kinds of machines
                share the file system Emacs is installed on.

`/usr/local/info' holds the on-line documentation for Emacs, known as
                "info files".  Many other GNU programs are documented
                using info files as well, so this directory stands
                apart from the other, Emacs-specific directories.

`/usr/local/man/man1' holds the man pages for the programs installed
                in `/usr/local/bin'.

If these directories are not what you want, you can specify where to
install Emacs's libraries and data files or where Emacs should search
for its lisp files by giving values for `make' variables as part of
the command.  See the section below called `MAKE VARIABLES' for more
information on this.

8) Check the file `dir' in your site's info directory (usually
/usr/local/info) to make sure that it has a menu entry for the Emacs
info files.

9) If your system uses lock files to interlock access to mailer inbox files,
then you might need to make the program arch-lib/movemail setuid or setgid
to enable it to write the lock files.  We believe this is safe.

10) You are done!


MAKE VARIABLES

You can change where the build process installs Emacs and its data
files by specifying values for `make' variables as part of the `make'
command line.  For example, if you type

    make install bindir=/usr/local/gnubin

the `bindir=/usr/local/gnubin' argument indicates that the Emacs
executable files should go in `/usr/local/gnubin', not
`/usr/local/bin'.

Here is a complete list of the variables you may want to set.

`bindir' indicates where to put executable programs that users can
        run.  This defaults to /usr/local/bin.

`datadir' indicates where to put the architecture-independent
        read-only data files that Emacs refers to while it runs; it
        defaults to /usr/local/lib.  We create the following
        subdirectories under `datadir':
        - `emacs/VERSION/lisp', containing the Emacs lisp library, and
        - `emacs/VERSION/etc', containing the Emacs tutorial, the DOC
                file, and the `yow' database.
        `VERSION' is the number of the Emacs version you are installing,
        like `18.59' or `19.0'.  Since these files vary from one version
        of Emacs to another, including the version number in the path
        allows you to have several versions of Emacs installed at the
        same time; this means that you don't have to make Emacs
        unavailable while installing a new version.

`statedir' indicates where to put architecture-independent data files
        that Emacs modifies while it runs; it defaults to
        /usr/local/lib as well.  We create the following
        subdirectories under `statedir':
        - `emacs/lock', containing files indicating who is editing
                what, so Emacs can detect editing clashes between
                users.

`libdir' indicates where to put architecture-specific data files that
        Emacs refers to as it runs; it too defaults to `/usr/local/lib'.
        We create the following subdirectories under `libdir':
        - `emacs/VERSION/CONFIGURATION-NAME', containing executable
                programs used by Emacs that users are not expected to run
                themselves.  
        `VERSION' is the number of the Emacs version you are installing,
        and `CONFIGURATION-NAME' is the argument you gave to the
        `configure' program to identify the architecture and operating
        system of your machine, like `mips-dec-ultrix' or
        `sparc-sun-sunos'.  Since these files are specific to the version
        of Emacs, operating system, and architecture in use, including
        the configuration name in the path allows you to have several
        versions of Emacs for any mix of machines and operating systems
        installed at the same time; this is useful for sites at which
        different kinds of machines share the file system Emacs is
        installed on.

`infodir' indicates where to put the info files distributed with
        Emacs; it defaults to `/usr/local/info'.

`mandir' indicates where to put the man pages for Emacs and its
        utilities (like `etags'); it defaults to
        `/usr/local/man/man1'.

`manext' gives the extension the man pages should be installed with.
        It should contain a period, followed by the appropriate
        digit.  It defaults to `.1'.  For example given the default
        values for `mandir' and `manext', the Emacs man page would be
        installed as `/usr/local/man/man1/emacs.1'.

`prefix' doesn't give a path for any specific part of Emacs; instead,
        its value is used to determine the defaults for all the
        architecture-independent path variables - `datadir',
        `statedir', `infodir', and `mandir'.  Its default value is
        `/usr/local'; the other variables add on `lib' or `man' to it
        by default.

        For example, suppose your site generally places GNU software
        under `/usr/users/software/gnusoft' instead of `/usr/local'.
        By including
            `prefix=/usr/users/software/gnusoft'
        in the arguments to `make', you can instruct the build process
        to place all of the Emacs data files in the appropriate
        directories under that path.

`exec_prefix' serves the same purpose as `prefix', but instead
        determines the default values for the architecture-dependent
        path variables - `bindir' and `libdir'.

The above variables serve analogous purposes in the makefiles for all
GNU software; here are some variables specific to Emacs.

`lispdir' indicates where Emacs installs and expects its lisp
        library.  Its default value, based on `datadir' (see above),
        is `/usr/local/lib/emacs/VERSION/lisp' (where `VERSION' is as
        described above).

`locallisppath' indicates where Emacs should search for lisp files
        specific to your site.  It should be a colon-separated list of
        directories; Emacs checks them in order before checking
        `lispdir'.  Its default value, based on `datadir' (see above),
        is `/usr/local/lib/emacs/site-lisp'.

`lisppath' is the complete list of directories Emacs should search for
        its lisp files; its default value is the concatenation of
        `lispdir' and `locallisppath'.  It should be a colon-separated
        list of directories; Emacs checks them in the order they
        appear.

`etcdir' indicates where Emacs should install and expect the rest of
        its architecture-independent data, like the tutorial, DOC
        file, and yow database.  Its default value, based on `datadir'
        (which see), is `/usr/local/lib/emacs/VERSION/etc'.

`lockdir' indicates the directory where Emacs keeps track of its
        locking information.  Its default value, based on `statedir'
        (which see), is `/usr/local/lib/emacs/lock'.

`archlibdir' indicates where Emacs installs and expects the
        executable files and other architecture-dependent data it uses
        while running.  Its default value, based on `libdir' (which
        see), is `/usr/local/lib/emacs/VERSION/CONFIGURATION-NAME'
        (where VERSION and CONFIGURATION-NAME are as described above).

Remember that you must specify any variable values you need each time
you run `make' in the top directory.  If you run `make' once to build
emacs, test it, and then run `make' again to install the files, you
must provide the same variable settings each time.  To make the
settings persist, you can edit them into the `Makefile' in the top
directory, but be aware that running the `configure' program erases
`Makefile' and rebuilds it from `Makefile.in'.

The top-level Makefile stores the variable settings it used in the
Makefiles for the subdirectories, so you don't have to specify them
when running make in the subdirectories.


CONFIGURATION BY HAND

Running the `configure' program performs the following steps.

1) Copy `./src/config.h.in' to `./src/config.h'.

2) Consult `./etc/MACHINES' to see what configuration name you should
use for your system.  Look at the code of the `configure' script to
see which operating system and architecture description files from
`src/s' and `src/m' should be used for that configuration name.  Edit
`src/config.h', and change the two `#include' directives to include
the appropriate system and architecture description files.

2) Edit `./src/config.h' to set the right options for your system.  If
you need to override any of the definitions in the s/*.h and m/*.h
files for your system and machine, do so by editing config.h, not by
changing the s/*.h and m/*.h files.  Occasionally you may need to
redefine parameters used in `./lib-src/movemail.c'.

3) If you're going to use the make utility to build Emacs, you will
still need to run `configure' first, giving theappropriate values for
the variables in the sections entitled "Things `configure' Might Edit"
and "Where To Install Things."  Note that you may only need to change
the variables `prefix' and `exec_prefix', since the rest of the
variables have reasonable defaults based on them.  For each Makefile
variable of this type, there is a corresponding configure option; for
example, to change the location of the lock directory, you might use

         ./configure --lockdir=/nfs/emacslock

4) If you're going to use the build-install script to build Emacs,
copy `./build-ins.in' to `./build-install', and edit the
definitions found at the top of the script.

The `configure' script is built from `configure.in' by the `autoconf'
program.  However, since Emacs has configuration requirements that
autoconf can't meet, `configure.in' uses an marriage of custom-baked
configuration code and autoconf macros.  New versions of autoconf
could very well break this arrangement, so it may be wise to avoid
rebuilding `configure' from `configure.in' when possible.


BUILDING GNU EMACS BY HAND

Once Emacs is configured, running `make' or running the shell script
`build-install' in the top directory performs the following steps.

1) Run `make src/paths.h' in the top directory.  This produces
`./src/paths.h' from the template file `./src/paths.h.in', changing
the paths to the values specified in `./Makefile'.

2) Cd to `./lib-src' and run `make'.  This creates executables named
`ctags' and `etags' and `wakeup' and `make-docfile' and `digest-doc'
and `test-distrib'.  And others.

3) Cd to `./src' and Run `make'.  This refers to files in the `./lisp'
and `./lib-src' subdirectories using names `../lisp' and
`../lib-src'.

This creates a file `./src/emacs' which is the runnable Emacs,
assigning it a new build version number by incrementing the build
version stored in `./lisp/version.el'.

It also creates a file in `./etc' whose name is `DOC' followed by the
current Emacs version.  This file contains documentation strings for
all the functions in Emacs.  Each time you run make to make a new
emacs, a new DOC file with a new name is made.  You must keep the DOC
file for an Emacs version as long as you keep using that Emacs
version.


INSTALLATION BY HAND

The steps below are done by the shell script `build-install' or by
running `make install' in the main directory of the Emacs
distribution.

1) Copy `./lisp' and its subdirectories, `./etc', and the executables
in `./lib-src' to their final destinations, as selected in `./src/paths.h'.

Strictly speaking, not all of the executables in `./lib-src' need be copied.
- The programs `cvtmail', `emacsserver', `fakemail', `hexl',
    `movemail', `timer', `vcdiff', `wakeup', and `yow' are used by
    Emacs; they do need to be copied.
- The programs `etags', `ctags', `emacsclient', `b2m', and `rcs2log'
    are intended to be run by users; they are handled below.
- The programs `make-docfile', `make-path', and `test-distrib' were
    used in building Emacs, and are not needed any more.
- The programs `digest-doc' and `sorted-doc' convert a `DOC' file into
    a file for users to read.  There is no important reason to move them.

2) Copy the files in `./info' to the place specified in
`./lisp/site-init.el' or `./lisp/paths.el'.  Note that if the
destination directory already contains a file named `dir', you
probably don't want to replace it with the `dir' file in the Emacs
distribution.  Instead, you should make sure that the existing `dir'
file contains an appropriate menu entry for the Emacs info.

3) Create a directory for Emacs to use for clash detection, named as
indicated by the PATH_LOCK macro in `./src/paths.h'.

4) Copy `./src/emacs' to `/usr/local/bin', or to some other directory
in users' search paths.  `./src/emacs' has an alternate name
`./src/emacs-EMACSVERSION'; you may wish to make a symbolic link named
`/usr/local/bin/emacs' pointing to that alternate name, as an easy way
of installing different versions.

You can delete `./src/temacs'.

5) Copy the programs `b2m', `emacsclient', `ctags', `etags', and
`rcs2log' from `./lib-src' to `/usr/local/bin'.  These programs are
intended for users to run.

6) Copy the man pages in `./etc' for emacs, ctags, and etags into the
appropriate man directories.

7) The files in the `./src' subdirectory, except for `emacs', are not
used by Emacs once it is built.  The source would be handy for
debugging.


PROBLEMS

See the file PROBLEMS in this directory for a list of various
problems sometimes encountered, and what to do about them.


Installation on MSDOG (a.k.a. MSDOS)

To install on MSDOG, you need to have the GNU C compiler for MSDOG
(also known as djgpp), GNU Make, rm, mv, chmod, and sed.  Type these
commands:

config msdos
make install

To save disk space, Emacs is built with the idea that you will execute
it from the same place in the file system where you built it.  As the
/usr/local/ subtree does not exist on most MSDOG systems, the
executables are placed in /emacs/bin/.

MSDOG is a not a multitasking operating system, so Emacs features such
as asynchronous subprocesses that depend on multitasking will not
work.  Synchronous subprocesses do work.