These are installation instructions for Bash.
-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' and `doc' directories, and the each
-directory under `lib'). 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.
-
-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.in' is used to create `configure' by a program
-called Autoconf. You only need `configure.in' 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 2.10 or newer.
-
-If you need to change `configure.in' or regenerate `configure', you
-will need to create two files: `_distribution' and `_patchlevel'.
-`_distribution' should contain the major and minor version numbers of
-the Bash distribution, for example `2.01'. `_patchlevel' should
-contain the patch level of the Bash distribution, `0' for example. The
-script `support/mkconffiles' has been provided to automate the creation
-of these files.
-
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.
+ 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 awhile. While running, it prints some
+ 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
+ 2. Type 'make' to compile Bash and build the 'bashbug' bug reporting
script.
- 3. Optionally, type `make tests' to run the Bash test suite.
+ 3. Optionally, type 'make tests' to run the Bash test suite.
- 4. Type `make install' to install `bash' and `bashbug'. This will
+ 4. Type 'make install' to install 'bash' and 'bashbug'. This will
also install the manual pages and Info file.
+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', 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-2.04$ ./configure --help
+
+at the Bash prompt in your Bash source directory.
+
+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 2.50 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'.
+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'.
+
+Next: Compiling For Multiple Architectures, Prev: Basic Installation, Up: Installing Bash
Compilers and Options
=====================
-Some systems require unusual options for compilation or linking that
-the `configure' script does not know about. You can give `configure'
+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:
+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.
+Next: Installation Names, Prev: Compilers and Options, Up: Installing Bash
+
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'
+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. 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 `..'.
+'--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 supports 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.
+If you have to use a 'make' that does not supports 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':
+'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
+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.
+Next: Specifying the System Type, Prev: Compiling For Multiple Architectures, Up: Installing Bash
+
Installation Names
==================
-By default, `make install' will install into `/usr/local/bin',
-`/usr/local/man', etc. You can specify an installation prefix other
-than `/usr/local' by giving `configure' the option `--prefix=PATH'.
+By default, 'make install' will install into '/usr/local/bin',
+'/usr/local/man', etc. You can specify an installation prefix other
+than '/usr/local' by giving 'configure' the option '--prefix=PATH', or
+by specifying a value for the 'DESTDIR' 'make' variable when running
+'make install'.
-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.
+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.
+
+Next: Sharing Defaults, Prev: Installation Names, Up: Installing Bash
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., `sparc-sun-sunos4.1.2').
+There may be some features 'configure' can not figure out automatically,
+but need 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.
-See the file `support/config.sub' for the possible values of each field.
+Next: Operation Controls, Prev: Specifying the System Type, Up: Installing Bash
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.
+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.
+
+Next: Optional Features, Prev: Sharing Defaults, Up: Installing Bash
Operation Controls
==================
-`configure' recognizes the following options to control how it operates.
+'configure' recognizes the following options to control how it operates.
-`--cache-file=FILE'
+'--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'.
+ './config.cache'. Set FILE to '/dev/null' to disable caching, for
+ debugging 'configure'.
-`--help'
- Print a summary of the options to `configure', and exit.
+'--help'
+ Print a summary of the options to 'configure', and exit.
-`--quiet'
-`--silent'
-`-q'
+'--quiet'
+'--silent'
+'-q'
Do not print messages saying which checks are being made.
-`--srcdir=DIR'
+'--srcdir=DIR'
Look for the Bash source code in directory DIR. Usually
- `configure' can determine that directory automatically.
+ 'configure' can determine that directory automatically.
-`--version'
- Print the version of Autoconf used to generate the `configure'
+'--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' also accepts some other, not widely used, boilerplate
+options. 'configure --help' prints the complete list.
+
+Prev: Operation Controls, Up: Installing Bash
Optional Features
=================
-The Bash `configure' has a number of `--enable-FEATURE' options, where
+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 `gnu-malloc'
-or `purify'. 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'.
+'--with-PACKAGE' options, where PACKAGE is something like 'bash-malloc'
+or 'purify'. 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.
+Here is a complete list of the '--enable-' and '--with-' options that
+the Bash 'configure' recognizes.
-`--with-afs'
+'--with-afs'
Define if you are using the Andrew File System from Transarc.
-`--with-curses'
+'--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 an
+ older version originally derived from the 4.2 BSD 'malloc'. This
+ 'malloc' is very fast, but wastes some space on each allocation.
+ 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. This should
be supplied if your system has an inadequate or incomplete termcap
database.
-`--with-glibc-malloc'
- Use the GNU libc version of `malloc' in `lib/malloc/gmalloc.c'.
- This is not the version of `malloc' that appears in glibc version
- 2, but a modified version of the `malloc' from glibc version 1.
- This is somewhat slower than the default `malloc', but wastes less
- space on a per-allocation basis, and will return memory to the
- operating system under some circumstances.
-
-`--with-gnu-malloc'
- Use the GNU version of `malloc' in `lib/malloc/malloc.c'. This is
- not the same `malloc' that appears in GNU libc, but an older
- version derived from the 4.2 BSD `malloc'. This `malloc' is very
- fast, but wastes some space on each allocation. 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-installed-readline'
- 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 4.0 and later versions.
-
-`--with-purify'
- Define this to use the Purify memory allocation checker from Pure
- Software.
-
-`--enable-minimal-config'
+'--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').
+
+'--with-purify'
+ Define this to use the Purify memory allocation checker from
+ Rational Software.
+
+'--enable-minimal-config'
This produces a shell with minimal features, close to the
historical Bourne shell.
-There are several `--enable-' options that alter how Bash is compiled
+There are several '--enable-' options that alter how Bash is compiled
and linked, rather than changing run-time features.
-`--enable-profiling'
+'--enable-largefile'
+ Enable support for large files
+ (http://www.sas.com/standards/large_file/x_open.20Mar96.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.
+ processed by 'gprof' each time it is executed.
-`--enable-static-link'
- This causes Bash to be linked statically, if `gcc' is being used.
+'--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'.
+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 'disabled-builtins',
+'direxpand-default', and 'xpg-echo-default' are enabled by default,
+unless the operating system does not provide the necessary support.
-All of the following options except for `disabled-builtins' and
-`usg-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-alias'
- Allow alias expansion and include the `alias' and `unalias'
- builtins (*note Aliases::.).
+'--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'
+'--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-brace-expansion'
- Include `csh'-like brace expansion ( `b{a,b}c' ==> `bac bbc' ).
- See *Note Brace Expansion::, for a complete description.
-
-`--enable-command-timing'
- Include support for recognizing `time' as a reserved word and for
- displaying timing statistics for the pipeline following `time'.
- This allows pipelines as well as shell builtins and functions to
- be timed.
-
-`--enable-cond-command'
- Include support for the `[[' conditional command (*note
- Conditional Constructs::.).
-
-`--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
+ Arrays::).
+
+'--enable-bang-history'
+ Include support for 'csh'-like history substitution (*note History
+ Interaction::).
+
+'--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 pipelines as well as shell
+ builtins and functions to be timed.
+
+'--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-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-dparen-arithmetic'
+ Include support for the '((...))' command (*note Conditional
+ Constructs::).
-`--enable-extended-glob'
+'--enable-extended-glob'
Include support for the extended pattern matching features
- described above under *Note Pattern Matching::.
-
-`--enable-help-builtin'
- Include the `help' builtin, which displays help on shell builtins
- and variables.
-
-`--enable-history'
- Include command history and the `fc' and `history' builtin
- commands.
-
-`--enable-job-control'
- This enables the job control features (*note Job Control::.), if
- the operating system supports them.
-
-`--enable-process-substitution'
- This enables process substitution (*note Process Substitution::.)
- if the operating system provides the necessary support.
-
-`--enable-prompt-string-decoding'
+ 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-asciirange-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 `$PS1', `$PS2', `$PS3', and `$PS4' prompt
- strings. See *Note Printing a Prompt::, for a complete list of
- prompt string escape sequences.
+ characters in the '$PS1', '$PS2', '$PS3', and '$PS4' prompt
+ strings. See *note Controlling the Prompt::, for a complete list
+ of prompt string escape sequences.
-`--enable-readline'
+'--enable-readline'
Include support for command-line editing and history with the Bash
- version of the Readline library (*note Command Line Editing::.).
+ version of the Readline library (*note Command Line Editing::).
-`--enable-restricted'
+'--enable-restricted'
Include support for a "restricted shell". If this is enabled,
- Bash, when called as `rbash', enters a restricted mode. See *Note
+ Bash, when called as 'rbash', enters a restricted mode. See *note
The Restricted Shell::, for a description of restricted mode.
-`--enable-select'
- Include the `select' builtin, which allows the generation of simple
- menus (*note Conditional Constructs::.).
-
-`--enable-usg-echo-default'
- Make the `echo' builtin expand backslash-escaped characters by
- default, without requiring the `-e' option. This makes the Bash
- `echo' behave more like the System V version.
-
-The file `config.h.top' 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.
+'--enable-select'
+ Include the 'select' compound command, which allows the generation
+ of simple menus (*note Conditional Constructs::).
+
+'--enable-separate-helpfiles'
+ Use external files for the documentation displayed by the 'help'
+ builtin instead of storing the text internally.
+
+'--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-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.