autoconf.texi

autoconf 2.59版,可用于redhat系统.用于编译原码,编写makefile文件.

@samp{$*}, and @strong{$%}.

@example
@group
$ @kbd{cat configure.ac}
AC_DEFINE(This, is, [an
[example]])
$ @kbd{autoconf -t 'AC_DEFINE:@@: $@@}
*: $*
$: $%'
@@: [This],[is],[an
[example]]
*: This,is,an
[example]
$: This:is:an [example]
@end group
@end example

@noindent
The @var{format} gives you a lot of freedom:

@example
@group
$ @kbd{autoconf -t 'AC_SUBST:$$ac_subst@{"$1"@} = "$f:$l";'}
$ac_subst@{"ECHO_C"@} = "configure.ac:2";
$ac_subst@{"ECHO_N"@} = "configure.ac:2";
$ac_subst@{"ECHO_T"@} = "configure.ac:2";
@i{More traces deleted}
@end group
@end example

@noindent
A long @var{separator} can be used to improve the readability of complex
structures, and to ease their parsing (for instance when no single
character is suitable as a separator):

@example
@group
$ @kbd{autoconf -t 'AM_MISSING_PROG:$@{|:::::|@}*'}
ACLOCAL|:::::|aclocal|:::::|$missing_dir
AUTOCONF|:::::|autoconf|:::::|$missing_dir
AUTOMAKE|:::::|automake|:::::|$missing_dir
@i{More traces deleted}
@end group
@end example

@node autoreconf Invocation
@section Using @command{autoreconf} to Update @command{configure} Scripts
@cindex @command{autoreconf}

Installing the various components of the @acronym{GNU} Build System can be
tedious: running @command{autopoint} for Gettext, @command{automake} for
@file{Makefile.in} etc.@: in each directory.  It may be needed either
because some tools such as @command{automake} have been updated on your
system, or because some of the sources such as @file{configure.ac} have
been updated, or finally, simply in order to install the @acronym{GNU} Build
System in a fresh tree.

@command{autoreconf} runs @command{autoconf}, @command{autoheader},
@command{aclocal}, @command{automake}, @command{libtoolize}, and
@command{autopoint} (when appropriate) repeatedly to update the
@acronym{GNU} Build System in the specified directories and their
subdirectories (@pxref{Subdirectories}).  By default, it only remakes
those files that are older than their sources.

If you install a new version of some tool, you can make
@command{autoreconf} remake @emph{all} of the files by giving it the
@option{--force} option.

@xref{Automatic Remaking}, for @file{Makefile} rules to automatically
remake @command{configure} scripts when their source files change.  That
method handles the timestamps of configuration header templates
properly, but does not pass @option{--autoconf-dir=@var{dir}} or
@option{--localdir=@var{dir}}.

@noindent
@command{autoreconf} accepts the following options:

@table @option
@item --help
@itemx -h
Print a summary of the command line options and exit.

@item --version
@itemx -V
Print the version number of Autoconf and exit.

@item --verbose
Print the name of each directory where @command{autoreconf} runs
@command{autoconf} (and @command{autoheader}, if appropriate).

@item --debug
@itemx -d
Don't remove the temporary files.

@item --force
@itemx -f
Remake even @file{configure} scripts and configuration headers that are
newer than their input files (@file{configure.ac} and, if present,
@file{aclocal.m4}).

@item --install
@itemx -i
Install the missing auxiliary files in the package.  By default, files
are copied; this can be changed with @option{--symlink}.

This option triggers calls to @samp{automake --add-missing},
@samp{libtoolize}, @samp{autopoint}, etc.

@item --symlink
@itemx -s
When used with @option{--install}, install symbolic links to the missing
auxiliary files instead of copying them.

@item --make
@itemx -m
When the directories were configured, update the configuration by
running @samp{./config.status --recheck && ./config.status}, and then
run @samp{make}.

@item --include=@var{dir}
@itemx -I @var{dir}
Append @var{dir} to the include path.  Multiple invocations accumulate.

@item --prepend-include=@var{dir}
@item -B @var{dir}
Prepend @var{dir} to the include path.  Multiple invocations accumulate.

@item --warnings=@var{category}
@itemx -W @var{category}
@evindex WARNINGS
Report the warnings related to @var{category} (which can actually be a
comma separated list).

@table @samp
@item cross
related to cross compilation issues.

@item obsolete
report the uses of obsolete constructs.

@item portability
portability issues

@item syntax
dubious syntactic constructs.

@item all
report all the warnings

@item none
report none

@item error
treats warnings as errors

@item no-@var{category}
disable warnings falling into @var{category}
@end table

Warnings about @samp{syntax} are enabled by default, and the environment
variable @code{WARNINGS}, a comma separated list of categories, is
honored.  Passing @samp{-W @var{category}} will actually behave as if
you had passed @samp{--warnings=syntax,$WARNINGS,@var{category}}.  If
you want to disable the defaults and @code{WARNINGS}, but (for example)
enable the warnings about obsolete constructs, you would use @option{-W
none,obsolete}.
@end table


@c ========================================= Initialization and Output Files.

@node Setup
@chapter Initialization and Output Files

Autoconf-generated @command{configure} scripts need some information about
how to initialize, such as how to find the package's source files and
about the output files to produce.  The following sections describe the
initialization and the creation of output files.

@menu
* Initializing configure::      Option processing etc.
* Notices::                     Copyright, version numbers in @command{configure}
* Input::                       Where Autoconf should find files
* Output::                      Outputting results from the configuration
* Configuration Actions::       Preparing the output based on results
* Configuration Files::         Creating output files
* Makefile Substitutions::      Using output variables in @file{Makefile}s
* Configuration Headers::       Creating a configuration header file
* Configuration Commands::      Running arbitrary instantiation commands
* Configuration Links::         Links depending on the configuration
* Subdirectories::              Configuring independent packages together
* Default Prefix::              Changing the default installation prefix
@end menu

@node Initializing configure
@section Initializing @command{configure}

Every @command{configure} script must call @code{AC_INIT} before doing
anything else.  The only other required macro is @code{AC_OUTPUT}
(@pxref{Output}).

@defmac AC_INIT (@var{package}, @var{version}, @ovar{bug-report}, @ovar{tarname})
@acindex{INIT}
Process any command-line arguments and perform various initializations
and verifications.

Set the name of the @var{package} and its @var{version}.  These are
typically used in @option{--version} support, including that of
@command{configure}.  The optional argument @var{bug-report} should be
the email to which users should send bug reports.  The package
@var{tarname} differs from @var{package}: the latter designates the full
package name (e.g., @samp{GNU Autoconf}), while the former is meant for
distribution tar ball names (e.g., @samp{autoconf}).  It defaults to
@var{package} with @samp{GNU } stripped, lower-cased, and all characters
other than alphanumerics and underscores are changed to @samp{-}.

It is preferable that the arguments of @code{AC_INIT} be static, i.e.,
there should not be any shell computation, but they can be computed by
M4.

The following M4 macros (e.g., @code{AC_PACKAGE_NAME}), output variables
(e.g., @code{PACKAGE_NAME}), and preprocessor symbols (e.g.,
@code{PACKAGE_NAME}) are defined by @code{AC_INIT}:

@table @asis
@item @code{AC_PACKAGE_NAME}, @code{PACKAGE_NAME}
@acindex{PACKAGE_NAME}
@ovindex PACKAGE_NAME
@cvindex PACKAGE_NAME
Exactly @var{package}.

@item @code{AC_PACKAGE_TARNAME}, @code{PACKAGE_TARNAME}
@acindex{PACKAGE_TARNAME}
@ovindex PACKAGE_TARNAME
@cvindex PACKAGE_TARNAME
Exactly @var{tarname}.

@item @code{AC_PACKAGE_VERSION}, @code{PACKAGE_VERSION}
@acindex{PACKAGE_VERSION}
@ovindex PACKAGE_VERSION
@cvindex PACKAGE_VERSION
Exactly @var{version}.

@item @code{AC_PACKAGE_STRING}, @code{PACKAGE_STRING}
@acindex{PACKAGE_STRING}
@ovindex PACKAGE_STRING
@cvindex PACKAGE_STRING
Exactly @samp{@var{package} @var{version}}.

@item @code{AC_PACKAGE_BUGREPORT}, @code{PACKAGE_BUGREPORT}
@acindex{PACKAGE_BUGREPORT}
@ovindex PACKAGE_BUGREPORT
@cvindex PACKAGE_BUGREPORT
Exactly @var{bug-report}.
@end table
@end defmac


@node Notices
@section Notices in @command{configure}

The following macros manage version numbers for @command{configure}
scripts.  Using them is optional.

@c FIXME: AC_PREREQ should not be here
@defmac AC_PREREQ (@var{version})
@acindex{PREREQ}
@cindex Version
Ensure that a recent enough version of Autoconf is being used.  If the
version of Autoconf being used to create @command{configure} is
earlier than @var{version}, print an error message to the standard
error output and exit with failure (exit status is 63).  For example:

@example
AC_PREREQ(@value{VERSION})
@end example

This macro is the only macro that may be used before @code{AC_INIT}, but
for consistency, you are invited not to do so.
@end defmac

@defmac AC_COPYRIGHT (@var{copyright-notice})
@acindex{COPYRIGHT}
@cindex Copyright Notice
State that, in addition to the Free Software Foundation's copyright on
the Autoconf macros, parts of your @command{configure} are covered by the
@var{copyright-notice}.

The @var{copyright-notice} will show up in both the head of
@command{configure} and in @samp{configure --version}.
@end defmac


@defmac AC_REVISION (@var{revision-info})
@acindex{REVISION}
@cindex Revision
Copy revision stamp @var{revision-info} into the @command{configure}
script, with any dollar signs or double-quotes removed.  This macro lets
you put a revision stamp from @file{configure.ac} into @command{configure}
without @acronym{RCS} or @acronym{CVS} changing it when you check in
@command{configure}.  That way, you can determine easily which revision of
@file{configure.ac} a particular @command{configure} corresponds to.

For example, this line in @file{configure.ac}:

@c The asis prevents RCS from changing the example in the manual.
@example
AC_REVISION($@asis{Revision: 1.30 }$)
@end example

@noindent
produces this in @command{configure}:

@example
#! /bin/sh
# From configure.ac Revision: 1.30
@end example
@end defmac


@node Input
@section Finding @command{configure} Input


@defmac AC_CONFIG_SRCDIR (@var{unique-file-in-source-dir})
@acindex{CONFIG_SRCDIR}
@var{unique-file-in-source-dir} is some file that is in the package's
source directory; @command{configure} checks for this file's existence to
make sure that the directory that it is told contains the source code in
fact does.  Occasionally people accidentally specify the wrong directory
with @option{--srcdir}; this is a safety check.  @xref{configure
Invocation}, for more information.
@end defmac


@c FIXME: Remove definitively once --install explained.
@c
@c Small packages may store all their macros in @code{aclocal.m4}.  As the
@c set of macros grows, or for maintenance reasons, a maintainer may prefer
@c to split the macros in several files.  In this case, Autoconf must be
@c told which files to load, and in which order.
@c
@c @defmac AC_INCLUDE (@var{file}@dot