Basic Installation
==================

These are installation instructions for Bash.

The simplest way to compile Bash is:

  1. ‘cd’ to the directory containing the source code and type
     ‘./configure’ to configure Bash for your system.  If you're using
     ‘csh’ on an old version of System V, you might need to type ‘sh
     ./configure’ instead to prevent ‘csh’ from trying to execute
     ‘configure’ itself.

     Running ‘configure’ takes some time.  While running, it prints
     messages telling which features it is checking for.

  2. Type ‘make’ to compile Bash and build the ‘bashbug’ bug reporting
     script.

  3. Optionally, type ‘make tests’ to run the Bash test suite.

  4. Type ‘make install’ to install ‘bash’ and ‘bashbug’.  This will
     also install the manual pages and Info file, message translation
     files, some supplemental documentation, a number of example
     loadable builtin commands, and a set of header files for developing
     loadable builtins.  You may need additional privileges to install
     ‘bash’ to your desired destination, which may require ‘sudo make
     install’.  More information about controlling the locations where
     ‘bash’ and other files are installed is below (*note Installation
     Names::).

The ‘configure’ shell script attempts to guess correct values for
various system-dependent variables used during compilation.  It uses
those values to create a ‘Makefile’ in each directory of the package
(the top directory, the ‘builtins’, ‘doc’, ‘po’, and ‘support’
directories, each directory under ‘lib’, and several others).  It also
creates a ‘config.h’ file containing system-dependent definitions.
Finally, it creates a shell script named ‘config.status’ that you can
run in the future to recreate the current configuration, a file
‘config.cache’ that saves the results of its tests to speed up
reconfiguring, and a file ‘config.log’ containing compiler output
(useful mainly for debugging ‘configure’).  If at some point
‘config.cache’ contains results you don't want to keep, you may remove
or edit it.

To find out more about the options and arguments that the ‘configure’
script understands, type

     bash-4.2$ ./configure --help

at the Bash prompt in your Bash source directory.

If you want to build Bash in a directory separate from the source
directory - to build for multiple architectures, for example - just use
the full path to the configure script.  The following commands will
build Bash in a directory under ‘/usr/local/build’ from the source code
in ‘/usr/local/src/bash-4.4’:

     mkdir /usr/local/build/bash-4.4
     cd /usr/local/build/bash-4.4
     bash /usr/local/src/bash-4.4/configure
     make

See *note Compiling For Multiple Architectures:: for more information
about building in a directory separate from the source.

If you need to do unusual things to compile Bash, please try to figure
out how ‘configure’ could check whether or not to do them, and mail
diffs or instructions to <bash-maintainers@gnu.org> so they can be
considered for the next release.

The file ‘configure.ac’ is used to create ‘configure’ by a program
called Autoconf.  You only need ‘configure.ac’ if you want to change it
or regenerate ‘configure’ using a newer version of Autoconf.  If you do
this, make sure you are using Autoconf version 2.69 or newer.

You can remove the program binaries and object files from the source
code directory by typing ‘make clean’.  To also remove the files that
‘configure’ created (so you can compile Bash for a different kind of
computer), type ‘make distclean’.

Compilers and Options
=====================

Some systems require unusual options for compilation or linking that the
‘configure’ script does not know about.  You can give ‘configure’
initial values for variables by setting them in the environment.  Using
a Bourne-compatible shell, you can do that on the command line like
this:

     CC=c89 CFLAGS=-O2 LIBS=-lposix ./configure

On systems that have the ‘env’ program, you can do it like this:

     env CPPFLAGS=-I/usr/local/include LDFLAGS=-s ./configure

The configuration process uses GCC to build Bash if it is available.

Compiling For Multiple Architectures
====================================

You can compile Bash for more than one kind of computer at the same
time, by placing the object files for each architecture in their own
directory.  To do this, you must use a version of ‘make’ that supports
the ‘VPATH’ variable, such as GNU ‘make’.  ‘cd’ to the directory where
you want the object files and executables to go and run the ‘configure’
script from the source directory (*note Basic Installation::).  You may
need to supply the ‘--srcdir=PATH’ argument to tell ‘configure’ where
the source files are.  ‘configure’ automatically checks for the source
code in the directory that ‘configure’ is in and in ‘..’.

If you have to use a ‘make’ that does not support the ‘VPATH’ variable,
you can compile Bash for one architecture at a time in the source code
directory.  After you have installed Bash for one architecture, use
‘make distclean’ before reconfiguring for another architecture.

Alternatively, if your system supports symbolic links, you can use the
‘support/mkclone’ script to create a build tree which has symbolic links
back to each file in the source directory.  Here's an example that
creates a build directory in the current directory from a source
directory ‘/usr/gnu/src/bash-2.0’:

     bash /usr/gnu/src/bash-2.0/support/mkclone -s /usr/gnu/src/bash-2.0 .

The ‘mkclone’ script requires Bash, so you must have already built Bash
for at least one architecture before you can create build directories
for other architectures.

Installation Names
==================

By default, ‘make install’ will install into ‘/usr/local/bin’,
‘/usr/local/man’, etc.; that is, the “installation prefix” defaults to
‘/usr/local’.  You can specify an installation prefix other than
‘/usr/local’ by giving ‘configure’ the option ‘--prefix=PATH’, or by
specifying a value for the ‘prefix’ ‘make’ variable when running ‘make
install’ (e.g., ‘make install prefix=PATH’).  The ‘prefix’ variable
provides a default for ‘exec_prefix’ and other variables used when
installing Bash.

You can specify separate installation prefixes for architecture-specific
files and architecture-independent files.  If you give ‘configure’ the
option ‘--exec-prefix=PATH’, ‘make install’ will use PATH as the prefix
for installing programs and libraries.  Documentation and other data
files will still use the regular prefix.

If you would like to change the installation locations for a single run,
you can specify these variables as arguments to ‘make’: ‘make install
exec_prefix=/’ will install ‘bash’ and ‘bashbug’ into ‘/bin’ instead of
the default ‘/usr/local/bin’.

If you want to see the files Bash will install and where it will install
them without changing anything on your system, specify the variable
‘DESTDIR’ as an argument to ‘make’.  Its value should be the absolute
directory path you'd like to use as the root of your sample installation
tree.  For example,

     mkdir /fs1/bash-install
     make install DESTDIR=/fs1/bash-install

will install ‘bash’ into ‘/fs1/bash-install/usr/local/bin/bash’, the
documentation into directories within
‘/fs1/bash-install/usr/local/share’, the example loadable builtins into
‘/fs1/bash-install/usr/local/lib/bash’, and so on.  You can use the
usual ‘exec_prefix’ and ‘prefix’ variables to alter the directory paths
beneath the value of ‘DESTDIR’.

The GNU Makefile standards provide a more complete description of these
variables and their effects.

Specifying the System Type
==========================

There may be some features ‘configure’ can not figure out automatically,
but needs to determine by the type of host Bash will run on.  Usually
‘configure’ can figure that out, but if it prints a message saying it
can not guess the host type, give it the ‘--host=TYPE’ option.  ‘TYPE’
can either be a short name for the system type, such as ‘sun4’, or a
canonical name with three fields: ‘CPU-COMPANY-SYSTEM’ (e.g.,
‘i386-unknown-freebsd4.2’).

See the file ‘support/config.sub’ for the possible values of each field.

Sharing Defaults
================

If you want to set default values for ‘configure’ scripts to share, you
can create a site shell script called ‘config.site’ that gives default
values for variables like ‘CC’, ‘cache_file’, and ‘prefix’.  ‘configure’
looks for ‘PREFIX/share/config.site’ if it exists, then
‘PREFIX/etc/config.site’ if it exists.  Or, you can set the
‘CONFIG_SITE’ environment variable to the location of the site script.
A warning: the Bash ‘configure’ looks for a site script, but not all
‘configure’ scripts do.

Operation Controls
==================

‘configure’ recognizes the following options to control how it operates.

‘--cache-file=FILE’
     Use and save the results of the tests in FILE instead of
     ‘./config.cache’.  Set FILE to ‘/dev/null’ to disable caching, for
     debugging ‘configure’.

‘--help’
     Print a summary of the options to ‘configure’, and exit.

‘--quiet’
‘--silent’
‘-q’
     Do not print messages saying which checks are being made.

‘--srcdir=DIR’
     Look for the Bash source code in directory DIR.  Usually
     ‘configure’ can determine that directory automatically.

‘--version’
     Print the version of Autoconf used to generate the ‘configure’
     script, and exit.

‘configure’ also accepts some other, not widely used, boilerplate
options.  ‘configure --help’ prints the complete list.

Optional Features
=================

The Bash ‘configure’ has a number of ‘--enable-FEATURE’ options, where
FEATURE indicates an optional part of Bash.  There are also several
‘--with-PACKAGE’ options, where PACKAGE is something like ‘bash-malloc’
or ‘afs’.  To turn off the default use of a package, use
‘--without-PACKAGE’.  To configure Bash without a feature that is
enabled by default, use ‘--disable-FEATURE’.

Here is a complete list of the ‘--enable-’ and ‘--with-’ options that
the Bash ‘configure’ recognizes.

‘--with-afs’
     Define if you are using the Andrew File System from Transarc.

‘--with-bash-malloc’
     Use the Bash version of ‘malloc’ in the directory ‘lib/malloc’.
     This is not the same ‘malloc’ that appears in GNU libc, but a
     custom version originally derived from the 4.2 BSD ‘malloc’.  This
     ‘malloc’ is very fast, but wastes some space on each allocation,
     though it uses several techniques to minimize the waste.  This
     option is enabled by default.  The ‘NOTES’ file contains a list of
     systems for which this should be turned off, and ‘configure’
     disables this option automatically for a number of systems.

‘--with-curses’
     Use the curses library instead of the termcap library.  ‘configure’
     usually chooses this automatically, since most systems include the
     termcap functions in the curses library.

‘--with-gnu-malloc’
     A synonym for ‘--with-bash-malloc’.

‘--with-installed-readline[=PREFIX]’
     Define this to make Bash link with a locally-installed version of
     Readline rather than the version in ‘lib/readline’.  This works
     only with Readline 5.0 and later versions.  If PREFIX is ‘yes’ or
     not supplied, ‘configure’ uses the values of the make variables
     ‘includedir’ and ‘libdir’, which are subdirectories of ‘prefix’ by
     default, to find the installed version of Readline if it is not in
     the standard system include and library directories.  If PREFIX is
     ‘no’, Bash links with the version in ‘lib/readline’.  If PREFIX is
     set to any other value, ‘configure’ treats it as a directory
     pathname and looks for the installed version of Readline in
     subdirectories of that directory (include files in PREFIX/‘include’
     and the library in PREFIX/‘lib’).  The Bash default is to link with
     a static library built in the ‘lib/readline’ subdirectory of the
     build directory.

‘--with-libintl-prefix[=PREFIX]’
     Define this to make Bash link with a locally-installed version of
     the libintl library instead of the version in ‘lib/intl’.

‘--with-libiconv-prefix[=PREFIX]’
     Define this to make Bash look for libiconv in PREFIX instead of the
     standard system locations.  The Bash distribution does not include
     this library.

‘--enable-minimal-config’
     This produces a shell with minimal features, closer to the
     historical Bourne shell.

There are several ‘--enable-’ options that alter how Bash is compiled,
linked, and installed, rather than changing run-time features.

‘--enable-largefile’
     Enable support for large files
     (http://www.unix.org/version2/whatsnew/lfs20mar.html) if the
     operating system requires special compiler options to build
     programs which can access large files.  This is enabled by default,
     if the operating system provides large file support.

‘--enable-profiling’
     This builds a Bash binary that produces profiling information to be
     processed by ‘gprof’ each time it is executed.

‘--enable-separate-helpfiles’
     Use external files for the documentation displayed by the ‘help’
     builtin instead of storing the text internally.

‘--enable-static-link’
     This causes Bash to be linked statically, if ‘gcc’ is being used.
     This could be used to build a version to use as root's shell.

The ‘minimal-config’ option can be used to disable all of the following
options, but it is processed first, so individual options may be enabled
using ‘enable-FEATURE’.

All of the following options except for ‘alt-array-implementation’,
‘disabled-builtins’, ‘direxpand-default’, ‘strict-posix-default’, and
‘xpg-echo-default’ are enabled by default, unless the operating system
does not provide the necessary support.

‘--enable-alias’
     Allow alias expansion and include the ‘alias’ and ‘unalias’
     builtins (*note Aliases::).

‘--enable-alt-array-implementation’
     This builds Bash using an alternate implementation of arrays (*note
     Arrays::) that provides faster access at the expense of using more
     memory (sometimes many times more, depending on how sparse an array
     is).

‘--enable-arith-for-command’
     Include support for the alternate form of the ‘for’ command that
     behaves like the C language ‘for’ statement (*note Looping
     Constructs::).

‘--enable-array-variables’
     Include support for one-dimensional array shell variables (*note
     Arrays::).

‘--enable-bang-history’
     Include support for ‘csh’-like history substitution (*note History
     Interaction::).

‘--enable-bash-source-fullpath-default’
     Set the default value of the ‘bash_source_fullpath’ shell option
     described above under *note The Shopt Builtin:: to be enabled.
     This controls how filenames are assigned to the ‘BASH_SOURCE’ array
     variable.

‘--enable-brace-expansion’
     Include ‘csh’-like brace expansion ( ‘b{a,b}c’ ↦ ‘bac bbc’ ).  See
     *note Brace Expansion::, for a complete description.

‘--enable-casemod-attributes’
     Include support for case-modifying attributes in the ‘declare’
     builtin and assignment statements.  Variables with the ‘uppercase’
     attribute, for example, will have their values converted to
     uppercase upon assignment.

‘--enable-casemod-expansion’
     Include support for case-modifying word expansions.

‘--enable-command-timing’
     Include support for recognizing ‘time’ as a reserved word and for
     displaying timing statistics for the pipeline following ‘time’
     (*note Pipelines::).  This allows timing pipelines, shell compound
     commands, shell builtins, and shell functions, which an external
     command cannot do easily.

‘--enable-cond-command’
     Include support for the ‘[[’ conditional command.  (*note
     Conditional Constructs::).

‘--enable-cond-regexp’
     Include support for matching POSIX regular expressions using the
     ‘=~’ binary operator in the ‘[[’ conditional command.  (*note
     Conditional Constructs::).

‘--enable-coprocesses’
     Include support for coprocesses and the ‘coproc’ reserved word
     (*note Pipelines::).

‘--enable-debugger’
     Include support for the Bash debugger (distributed separately).

‘--enable-dev-fd-stat-broken’
     If calling ‘stat’ on /dev/fd/N returns different results than
     calling ‘fstat’ on file descriptor N, supply this option to enable
     a workaround.  This has implications for conditional commands that
     test file attributes.

‘--enable-direxpand-default’
     Cause the ‘direxpand’ shell option (*note The Shopt Builtin::) to
     be enabled by default when the shell starts.  It is normally
     disabled by default.

‘--enable-directory-stack’
     Include support for a ‘csh’-like directory stack and the ‘pushd’,
     ‘popd’, and ‘dirs’ builtins (*note The Directory Stack::).

‘--enable-disabled-builtins’
     Allow builtin commands to be invoked via ‘builtin xxx’ even after
     ‘xxx’ has been disabled using ‘enable -n xxx’.  See *note Bash
     Builtins::, for details of the ‘builtin’ and ‘enable’ builtin
     commands.

‘--enable-dparen-arithmetic’
     Include support for the ‘((...))’ command (*note Conditional
     Constructs::).

‘--enable-extended-glob’
     Include support for the extended pattern matching features
     described above under *note Pattern Matching::.

‘--enable-extended-glob-default’
     Set the default value of the ‘extglob’ shell option described above
     under *note The Shopt Builtin:: to be enabled.

‘--enable-function-import’
     Include support for importing function definitions exported by
     another instance of the shell from the environment.  This option is
     enabled by default.

‘--enable-glob-asciiranges-default’
     Set the default value of the ‘globasciiranges’ shell option
     described above under *note The Shopt Builtin:: to be enabled.
     This controls the behavior of character ranges when used in pattern
     matching bracket expressions.

‘--enable-help-builtin’
     Include the ‘help’ builtin, which displays help on shell builtins
     and variables (*note Bash Builtins::).

‘--enable-history’
     Include command history and the ‘fc’ and ‘history’ builtin commands
     (*note Bash History Facilities::).

‘--enable-job-control’
     This enables the job control features (*note Job Control::), if the
     operating system supports them.

‘--enable-multibyte’
     This enables support for multibyte characters if the operating
     system provides the necessary support.

‘--enable-net-redirections’
     This enables the special handling of filenames of the form
     ‘/dev/tcp/HOST/PORT’ and ‘/dev/udp/HOST/PORT’ when used in
     redirections (*note Redirections::).

‘--enable-process-substitution’
     This enables process substitution (*note Process Substitution::) if
     the operating system provides the necessary support.

‘--enable-progcomp’
     Enable the programmable completion facilities (*note Programmable
     Completion::).  If Readline is not enabled, this option has no
     effect.

‘--enable-prompt-string-decoding’
     Turn on the interpretation of a number of backslash-escaped
     characters in the ‘$PS0’, ‘$PS1’, ‘$PS2’, and ‘$PS4’ prompt
     strings.  See *note Controlling the Prompt::, for a complete list
     of prompt string escape sequences.

‘--enable-readline’
     Include support for command-line editing and history with the Bash
     version of the Readline library (*note Command Line Editing::).

‘--enable-restricted’
     Include support for a “restricted shell”.  If this is enabled, Bash
     enters a restricted mode when called as ‘rbash’.  See *note The
     Restricted Shell::, for a description of restricted mode.

‘--enable-select’
     Include the ‘select’ compound command, which allows generation of
     simple menus (*note Conditional Constructs::).

‘--enable-single-help-strings’
     Store the text displayed by the ‘help’ builtin as a single string
     for each help topic.  This aids in translating the text to
     different languages.  You may need to disable this if your compiler
     cannot handle very long string literals.

‘--enable-strict-posix-default’
     Make Bash POSIX-conformant by default (*note Bash POSIX Mode::).

‘--enable-translatable-strings’
     Enable support for ‘$"STRING"’ translatable strings (*note Locale
     Translation::).

‘--enable-usg-echo-default’
     A synonym for ‘--enable-xpg-echo-default’.

‘--enable-xpg-echo-default’
     Make the ‘echo’ builtin expand backslash-escaped characters by
     default, without requiring the ‘-e’ option.  This sets the default
     value of the ‘xpg_echo’ shell option to ‘on’, which makes the Bash
     ‘echo’ behave more like the version specified in the Single Unix
     Specification, version 3.  *Note Bash Builtins::, for a description
     of the escape sequences that ‘echo’ recognizes.

The file ‘config-top.h’ contains C Preprocessor ‘#define’ statements for
options which are not settable from ‘configure’.  Some of these are not
meant to be changed; beware of the consequences if you do.  Read the
comments associated with each definition for more information about its
effect.
