------------------------------------------------------------------------------
-* Fix AC_ARG_{ENABLE,WITH}, and AC_PATH_X*, and AC_REQUIRE
- interrupting messages.
+* Fix AC_ARG_{ENABLE,WITH}, and AC_REQUIRE interrupting messages.
------------------------------------------------------------------------------
\f
------------------------------------------------------------------------------
+* Add a --indent option to autoconf to call shindent.
+
+------------------------------------------------------------------------------
+
+* Doc: Add indexes of concepts, env vars.
+
+------------------------------------------------------------------------------
+
* Supply a template Makefile.in that people can adapt (what GNU hello
was going to be).
dnl
AC_DEFUN(AC_PATH_X,
[AC_REQUIRE_CPP()dnl Set CPP; we run AC_PATH_X_DIRECT conditionally.
-# If we find X, set shell vars x_includes and x_libraries to the paths.
-no_x=yes
-if test "x$with_x" != xno; then
+# If we find X, set shell vars x_includes and x_libraries to the
+# paths, otherwise set no_x=yes.
+# Uses ac_ vars as temps to allow command line to override cache and checks.
+# --without-x overrides everything else, but does not touch the cache.
+AC_MSG_CHECKING(for X)
-# Command line options override cache.
-# FIXME We need to allow --x=includes= to work, I think.
-test -n "$x_includes" && ac_cv_x_includes="$x_includes"
-test -n "$x_libraries" && ac_cv_x_includes="$x_libraries"
-if test "${ac_cv_x_includes+set}" = set &&
- test "${ac_cv_x_libraries+set}" = set; then
- AC_VERBOSE(using cached values for ac_cv_x_includes and ac_cv_x_libraries)
+if test "x$with_x" = xno; then
+ no_x=yes
else
+ if test "x$x_includes" != xNONE && test "x$x_libraries" != xNONE; then
+ no_x=
+ else
+AC_CACHE_VAL(ac_cv_path_x,
+[# One or both of the vars are not set, and there is no cached value.
+no_x=yes
AC_PATH_X_XMKMF
-fi
-if test "${ac_cv_x_includes+set}" != set ||
- test "${ac_cv_x_libraries+set}" != set; then
+if test "$no_x" = yes; then
AC_PATH_X_DIRECT
fi
-test -z "$ac_cv_x_includes" && ac_cv_x_includes=NONE
-test -z "$ac_cv_x_libraries" && ac_cv_x_libraries=NONE
+if test "$no_x" = yes; then
+ ac_cv_path_x="no_x=yes"
+else
+ ac_cv_path_x="no_x= ac_x_includes=$ac_x_includes ac_x_libraries=$ac_x_libraries"
+fi])dnl
+ fi
+ eval "$ac_cv_path_x"
+fi # $with_x != no
-# FIXME can we reliably distinguish cache values that are set to empty
-# from those that aren't set?
-if test -z "$x_includes" && test "$ac_cv_x_includes" != NONE; then
- x_includes="$ac_cv_x_includes"
-fi
-if test -z "$x_libraries" && test "$ac_cv_x_libraries" != NONE; then
- x_libraries="$ac_cv_x_libraries"
+if test "$no_x" = yes; then
+ AC_MSG_RESULT(no)
+else
+ test "x$x_includes" = xNONE && x_includes=$ac_x_includes
+ test "x$x_libraries" = xNONE && x_libraries=$ac_x_libraries
+ ac_cv_path_x="no_x= ac_x_includes=$x_includes ac_x_libraries=$x_libraries"
+ AC_MSG_RESULT([libraries $x_libraries, headers $x_includes])
fi
-
-test -n "$x_includes" && AC_VERBOSE(X11 headers are in $x_includes)
-test -n "$x_libraries" && AC_VERBOSE(X11 libraries are in $x_libraries)
-fi # No --with-x=no.
])dnl
dnl
dnl Internal subroutine of AC_PATH_X.
+dnl Set ac_x_includes, ac_x_libraries, and no_x (initially yes).
AC_DEFUN(AC_PATH_X_XMKMF,
-[AC_CHECKING(for X include and library files with xmkmf)
-rm -fr conftestdir
+[rm -fr conftestdir
if mkdir conftestdir; then
cd conftestdir
# Make sure to not put "make" in the Imakefile rules, since we grep it out.
fi
case "$ac_im_incroot" in
/usr/include) ;;
- *) test -z "$ac_cv_x_includes" && ac_cv_x_includes="$ac_im_incroot" ;;
+ *) ac_x_includes="$ac_im_incroot" ;;
esac
case "$ac_im_usrlibdir" in
/usr/lib | /lib) ;;
- *) test -z "$ac_cv_x_libraries" && ac_cv_x_libraries="$ac_im_usrlibdir" ;;
+ *) ac_x_libraries="$ac_im_usrlibdir" ;;
esac
fi
cd ..
])dnl
dnl
dnl Internal subroutine of AC_PATH_X.
+dnl Set ac_x_includes, ac_x_libraries, and no_x (initially yes).
AC_DEFUN(AC_PATH_X_DIRECT,
-[AC_CHECKING(for X include and library files directly)
-test -z "$x_direct_test_library" && x_direct_test_library=Xt
+[test -z "$x_direct_test_library" && x_direct_test_library=Xt
test -z "$x_direct_test_include" && x_direct_test_include=X11/Intrinsic.h
-AC_TRY_CPP([#include <$x_direct_test_include>], no_x=,
- for ac_dir in \
+AC_TRY_CPP([#include <$x_direct_test_include>], [no_x= ac_x_includes=],
+[ for ac_dir in \
/usr/X11R6/include \
/usr/X11R5/include \
/usr/X11R4/include \
; \
do
if test -r "$ac_dir/$x_direct_test_include"; then
- test -z "$ac_cv_x_includes" && ac_cv_x_includes=$ac_dir
- no_x=
+ no_x= ac_x_includes=$ac_dir
break
fi
- done)
+ done])
# Check for the libraries. First see if replacing the include by
# lib works.
-AC_HAVE_LIBRARY("$x_direct_test_library", no_x=,
-for ac_dir in `echo "$ac_cv_x_includes" | sed s/include/lib/` \
+AC_CHECK_LIB("$x_direct_test_library", main, [no_x= ac_x_libraries=],
+[for ac_dir in `echo "$ac_x_includes" | sed s/include/lib/` \
/usr/X11R6/lib \
/usr/X11R5/lib \
/usr/X11R4/lib \
do
for ac_extension in a so sl; do
if test -r $ac_dir/lib${x_direct_test_library}.$ac_extension; then
- test -z "$ac_cv_x_libraries" && ac_cv_x_libraries=$ac_dir
- no_x=
+ no_x= ac_x_libraries=$ac_dir
break 2
fi
done
-done)])dnl
+done])])dnl
dnl
dnl Find additional X libraries, magic flags, etc.
AC_DEFUN(AC_PATH_XTRA,
[AC_REQUIRE([AC_OS_ISC])dnl
AC_REQUIRE([AC_PATH_X])dnl
AC_CHECKING(for additional X libraries and flags)
-if test -n "$x_includes"; then
- X_CFLAGS="$X_CFLAGS -I$x_includes"
-elif test "$no_x" = yes; then
+if test "$no_x" = yes; then
# Not all programs may use this symbol, but it does not hurt to define it.
X_CFLAGS="$X_CFLAGS -DX_DISPLAY_MISSING"
-fi
+else
+ if test -n "$x_includes"; then
+ X_CFLAGS="$X_CFLAGS -I$x_includes"
+ fi
-# It would be nice to have a more robust check for the -R ld option than
-# just checking for Solaris.
-# It would also be nice to do this for all -L options, not just this one.
-if test -n "$x_libraries"; then
- X_LIBS="$X_LIBS -L$x_libraries"
- if test "`(uname) 2>/dev/null`" = SunOS &&
- uname -r | grep '^5' >/dev/null; then
- X_LIBS="$X_LIBS -R$x_libraries"
+ # It would be nice to have a more robust check for the -R ld option than
+ # just checking for Solaris.
+ # It would also be nice to do this for all -L options, not just this one.
+ if test -n "$x_libraries"; then
+ X_LIBS="$X_LIBS -L$x_libraries"
+ if test "`(uname) 2>/dev/null`" = SunOS &&
+ uname -r | grep '^5' >/dev/null; then
+ X_LIBS="$X_LIBS -R$x_libraries"
+ fi
fi
-fi
-# Check for additional X libraries.
+ # Check for additional X libraries.
-if test "$ISC" = yes; then
- X_EXTRA_LIBS="$X_EXTRA_LIBS -lnsl_s -linet"
-else
- # Martyn.Johnson@cl.cam.ac.uk says this is needed for Ultrix, if the X
- # libraries were built with DECnet support. And karl@cs.umb.edu says
- # the Alpha needs dnet_stub (dnet does not exist).
- AC_CHECK_LIB(dnet, dnet_ntoa,
- [X_EXTRA_LIBS="$X_EXTRA_LIBS -ldnet" ac_have_dnet=yes], ac_have_dnet=no)
- if test "$ac_have_dnet" = no; then
- AC_CHECK_LIB(dnet_stub, dnet_ntoa,
- [X_EXTRA_LIBS="$X_EXTRA_LIBS -ldnet_stub"])
- fi
- # lieder@skyler.mavd.honeywell.com says without -lsocket,
- # socket/setsockopt and other routines are undefined under SCO ODT 2.0.
- # But -lsocket is broken on IRIX, according to simon@lia.di.epfl.ch.
- if test "`(uname) 2>/dev/null`" != IRIX; then
- AC_CHECK_LIB(socket, socket, [X_EXTRA_LIBS="$X_EXTRA_LIBS -lsocket"])
+ if test "$ISC" = yes; then
+ X_EXTRA_LIBS="$X_EXTRA_LIBS -lnsl_s -linet"
+ else
+ # Martyn.Johnson@cl.cam.ac.uk says this is needed for Ultrix, if the X
+ # libraries were built with DECnet support. And karl@cs.umb.edu says
+ # the Alpha needs dnet_stub (dnet does not exist).
+ AC_CHECK_LIB(dnet, dnet_ntoa,
+ [X_EXTRA_LIBS="$X_EXTRA_LIBS -ldnet" ac_have_dnet=yes], ac_have_dnet=no)
+ if test "$ac_have_dnet" = no; then
+ AC_CHECK_LIB(dnet_stub, dnet_ntoa,
+ [X_EXTRA_LIBS="$X_EXTRA_LIBS -ldnet_stub"])
+ fi
+ # lieder@skyler.mavd.honeywell.com says without -lsocket,
+ # socket/setsockopt and other routines are undefined under SCO ODT 2.0.
+ # But -lsocket is broken on IRIX, according to simon@lia.di.epfl.ch.
+ if test "`(uname) 2>/dev/null`" != IRIX; then
+ AC_CHECK_LIB(socket, socket, [X_EXTRA_LIBS="$X_EXTRA_LIBS -lsocket"])
+ fi
fi
fi
-#
-AC_VERBOSE(X compiler flags: $X_CFLAGS)
-AC_VERBOSE(X library flags: $X_LIBS)
-AC_VERBOSE(extra X libraries: $X_EXTRA_LIBS)
AC_SUBST(X_CFLAGS)dnl
AC_SUBST(X_LIBS)dnl
AC_SUBST(X_EXTRA_LIBS)dnl
* Site Default Values:: Providing local defaults for @code{configure}.
* Old Macro Names:: Backward compatibility macros.
* Example:: Sample Autoconf input files.
+* History:: History of Autoconf.
* Preprocessor Symbol Index:: Index of C preprocessor symbols defined.
* Macro Index:: Index of Autoconf macros.
* Sample configure.in:: An example of a @file{configure} template.
* Sample Makefile.in:: An example of a @file{Makefile} template.
+
+History of Autoconf
+
+* Genesis:: Prehistory and naming of @code{configure}.
+* Exodus:: The plagues of @code{m4} and Perl.
+* Leviticus:: The priestly code of portability arrives.
+* Numbers:: Listing of growth and contributors.
+* Deuteronomy:: Approaching the promises of easy configuration.
@end menu
@node Introduction, Distributing, Top, Top
If this macro finds @file{alloca.h}, it defines @code{HAVE_ALLOCA_H}.
-This macro does not try to get @code{alloca} from the SVR3 @file{libPW}
-or the SVR4 @file{libucb} because those libraries contain some
-incompatible functions that cause trouble. Some versions do not even
-contain @code{alloca} or contain a buggy version. If you still want to
-use their @code{alloca}, use @code{ar} to extract @file{alloca.o} from
-them instead of compiling @file{alloca.c}.
+This macro does not try to get @code{alloca} from the System V R3
+@file{libPW} or the System V R4 @file{libucb} because those libraries
+contain some incompatible functions that cause trouble. Some versions
+do not even contain @code{alloca} or contain a buggy version. If you
+still want to use their @code{alloca}, use @code{ar} to extract
+@file{alloca.o} from them instead of compiling @file{alloca.c}.
Source files that use @code{alloca} should start with a piece of code
like the following, to declare it properly. Note that in some versions
whether it found a match.
To check whether the Autoconf macros have already defined a certain C
-preprocessor symbol, you can use a @code{case} statement like this:
+preprocessor symbol, test the value of the appropriate cache variable,
+as in this example:
@example
-case "$DEFS" in
- *HAVE_FOO*) ;;
- *) LIBOBJS="$LIBOBJS foo.o" ;;
-esac
+AC_CHECK_FUNC(vprintf, AC_DEFINE(HAVE_VPRINTF))
+if test "$ac_cv_func_vprintf" != yes; then
+AC_CHECK_FUNC(_doprnt, AC_DEFINE(HAVE_DOPRNT))
+fi
@end example
@noindent
-Make sure to enclose the variable name you are checking (usually
-@code{DEFS}) in double quotes, because otherwise some old versions of
-@code{bash} misinterpret the statement.
+Unlike in Autoconf version 1, there is no shell variable @code{DEFS} set
+while @code{configure} is running. This difference is because properly
+quoting the contents of that variable turned out to be too cumbersome to
+do every time @code{AC_DEFINE} is called.
@node Test Programs, Multiple Cases, Checking for Symbols, Writing Macros
@section Test Programs
@code{AC_OS_DYNIX}
@end table
-@node Example, Preprocessor Symbol Index, Old Macro Names, Top
+@node Example, History, Old Macro Names, Top
@chapter An Example
Here are sample @file{configure.in} and @file{Makefile.in} files, to
CFLAGS = -g
LDFLAGS = -g
-prefix = /usr/local
-exec_prefix = $(prefix)
+prefix = @@prefix@@
+exec_prefix = @@exec_prefix@@
binprefix =
manprefix =
rm -rf `cat .fname` .fname
@end example
-@node Preprocessor Symbol Index, Macro Index, Example, Top
+@node History, Preprocessor Symbol Index, Example, Top
+@chapter History of Autoconf
+
+You may be wondering, Why was Autoconf originally written? How did it
+get into its present form? (Why does it look like gorilla spit?) If
+you're not wondering, then this chapter contains no information useful
+to you, and you might as well skip it. If you @emph{are} wondering,
+then let there be light.
+
+@menu
+* Genesis:: Prehistory and naming of @code{configure}.
+* Exodus:: The plagues of @code{m4} and Perl.
+* Leviticus:: The priestly code of portability arrives.
+* Numbers:: Listing of growth and contributors.
+* Deuteronomy:: Approaching the promises of easy configuration.
+@end menu
+
+@node Genesis, Exodus, , History
+@section Genesis
+
+In June 1991 I was maintaining many of the GNU utilities for the Free
+Software Foundation. As they were ported to more platforms and more
+programs were added, the number of @samp{-D} options that users had to
+select in the @file{Makefile} (around 20) became burdensome. Especially
+for me---I had to test each new release on a bunch of different systems.
+So I wrote a little shell script to guess some of the correct settings
+for the fileutils package, and released it as part of fileutils 2.0.
+That @code{configure} script worked well enough that the next month I
+adapted it (by hand) to create similar @code{configure} scripts for
+several other GNU utilities packages. Brian Berliner also adapted one
+of my scripts for his CVS revision control system.
+
+Later that summer, I learned that Richard Stallman and Richard Pixley
+were developing similar scripts to use in the GNU compiler tools; so I
+adapted my @code{configure} scripts to support their evolving interface:
+using the file name @file{Makefile.in} as the templates; adding
+@samp{+srcdir}, the first option (of many); and creating
+@file{config.status} files.
+
+@node Exodus, Leviticus, Genesis, History
+@section Exodus
+
+As I got feedback from users, I incorporated many improvements, using
+Emacs to search and replace, cut and paste, similar changes in each of
+the scripts. As I adapted more GNU utilities packages to use
+@code{configure} scripts, updating them all by hand became burdensome.
+Rich Murphey, the maintainer of the GNU graphics utilities, sent me mail
+saying that the @code{configure} scripts were great, and asking if I had
+a program for generating them that I could send him. No, I thought, but
+I should! So I started to work out how to generate them. And the
+journey from the bondage of hand-written @file{configure} scripts to the
+promise of Autoconf began.
+
+I looked briefly into using Larry Wall's Metaconfig program, but I
+decided not to for several reasons. The @code{Configure} scripts it
+produces are interactive, which I find quite inconvenient; I didn't like
+the ways it checked for some features (such as library functions); it
+was not being maintained, and its scripts didn't work on many modern
+systems (such as System V R4 and NeXT); it wasn't very flexible in what
+it could do in response to a feature's presence or absence; I found it
+confusing to learn; and it was too big and complex for my needs (I
+didn't realize then how much Autoconf would eventually have to grow). I
+considered using Perl to generate my style of @code{configure} scripts,
+but decided that @code{m4} was better suited to the job of simple
+textual substitutions: it gets in the way less, because output is
+implicit. Plus, everyone already has it. (Initially I didn't rely on
+the GNU extensions to @code{m4}.) Also, some of my friends at the
+University of Maryland had recently been putting @code{m4} front ends on
+several programs, including @code{tvtwm}, and I was interested in trying
+out a new language.
+
+@node Leviticus, Numbers, Exodus, History
+@section Leviticus
+
+Since my @code{configure} scripts determine the system's capabilities
+automatically, with no interactive user intervention, I decided to call
+the program that generates them Autoconfig. But with a version number
+tacked on, that name would be too long for System V R3 file systems, so
+I shortened it to Autoconf.
+
+I called together a group of priests of portability (er, alpha testers)
+to give me feedback as I encapsulated pieces of my handwritten scripts
+in @code{m4} macros and continued to add features and improve the
+techniques used in the checks. Prominent among the testers were
+@ifinfo
+Franc,ois
+@end ifinfo
+@tex
+Fran\c cois
+@end tex
+Pinard, who came up with the idea of making an @file{autoconf} shell
+script to run @code{m4} and check for unresolved macro calls; Karl
+Berry, who championed standardizing the @code{HAVE_@var{feature}} form
+for C preprocessor symbols; and Ian Taylor, who added support for
+creating a C header file as an alternative to putting @samp{-D} options
+in a @file{Makefile}, so he could use it in his UUCP package. The alpha
+testers cheerfully adjusted their files again and again as the names and
+calling conventions of the Autoconf macros changed from release to
+release. They all contributed many specific checks, great ideas, and
+bug fixes.
+
+@node Numbers, Deuteronomy, Leviticus, History
+@section Numbers
+
+In July 1992, after months of alpha testing, I released Autoconf 1.0,
+and converted many of GNU packages to use it. I was surprised by how
+positive the reaction to it was. More people started using it than I
+could keep track of, including people working on software that wasn't
+part of the GNU Project (such as TCL, FSP, @TeX{}, and Kerberos v5).
+Autoconf continued to improve rapidly, as many people using the
+@code{configure} scripts reported problems they encountered.
+
+Autoconf turned out to be a good torture test for @code{m4}
+implementations. Unix @code{m4} started to dump core because of the
+length of the macros that Autoconf defined, and several bugs showed up
+in GNU @code{m4} as well. Eventually, we realized that we needed to use
+some features that only GNU @code{m4} has. BSD @code{m4}, in
+particular, has an impoverished set of builtin macros; the System V
+version is better, but still doesn't have everything we need.
+
+More development occurred as people put Autoconf under more stresses
+(and to uses I'd never imagined). Karl Berry added checks for X11.
+david zuhn contributed C++ support.
+@ifinfo
+Franc,ois
+@end ifinfo
+@tex
+Fran\c cois
+@end tex
+Pinard made it diagnose invalid arguments. Jim Blandy bravely coerced
+it into configuring GNU Emacs, laying the groundwork for several later
+improvements. Roland McGrath got it to configure the GNU C Library,
+wrote the @code{autoheader} script to automate the creation of C header
+file templates, and added a @samp{--verbose} option to @code{configure}.
+Noah Friedman added the @samp{--macrodir} option and @code{AC_MACRODIR}
+environment variable. Roland and Noah improved the quoting protection
+in @code{AC_DEFINE} and fixed many bugs, especially when I got sick of
+dealing with portability problems from February through June, 1993.
+
+@node Deuteronomy, , Numbers, History
+@section Deuteronomy
+
+A long wish list for major features had accumulated, and the effect of
+several years of patching by various people had left some residual
+cruft. In April 1994, while working for Cygnus Support, I began a major
+revision of Autoconf. I added most of the features of the Cygnus
+@code{configure} that Autoconf had lacked; for example, support for
+using @file{config.sub} and options like @samp{--host}, derived from
+work that david zuhn and Ken Raeburn contributed while converting GNU
+@code{as} to use Autoconf. Rob Savoye required the ability to run
+@code{configure} scripts in subdirectories when he made DejaGNU use
+Autoconf.
+
+I added more features in response to other peoples' requests. Many
+people had asked for @code{configure} scripts to share the results of
+the checks between runs, because (particularly when configuring a large
+source tree, like Cygnus does) they were frustratingly slow. Mike
+Haertel suggested adding site-specific initialization scripts. People
+distributing software that had to unpack on MS-DOS asked for a way to
+override the @file{.in} extension on the file names. Jim Avera did an
+extensive examination of the problems with quoting in @code{AC_DEFINE}
+and contributed significant improvements to it. Richard Stallman asked
+that compiler output be sent to @file{config.log} instead of
+@file{/dev/null}, to help people debug the Emacs @code{configure}
+script.
+
+I made some other changes because of my dissatisfaction with the quality
+of the program. I made the messages showing results of the checks less
+ambiguous, always printing a result. I regularized the names of the
+macros and cleaned up coding style inconsistencies. I added several
+useful auxiliary utilities that I had developed to help convert source
+code packages to use Autoconf. And I began a testsuite, because
+experience had shown that Autoconf had a pronounced tendency to regress
+when we changed it.
+
+Again, several alpha testers gave invaluable feedback, especially
+@ifinfo
+Franc,ois
+@end ifinfo
+@tex
+Fran\c cois
+@end tex
+Pinard, Rob Savoye, and Ken Raeburn.
+
+Finally, version 2.0 was ready.
+
+@node Preprocessor Symbol Index, Macro Index, History, Top
@unnumbered Preprocessor Symbol Index
This is an alphabetical list of the C preprocessor symbols that the
* Site Default Values:: Providing local defaults for @code{configure}.
* Old Macro Names:: Backward compatibility macros.
* Example:: Sample Autoconf input files.
+* History:: History of Autoconf.
* Preprocessor Symbol Index:: Index of C preprocessor symbols defined.
* Macro Index:: Index of Autoconf macros.
* Sample configure.in:: An example of a @file{configure} template.
* Sample Makefile.in:: An example of a @file{Makefile} template.
+
+History of Autoconf
+
+* Genesis:: Prehistory and naming of @code{configure}.
+* Exodus:: The plagues of @code{m4} and Perl.
+* Leviticus:: The priestly code of portability arrives.
+* Numbers:: Listing of growth and contributors.
+* Deuteronomy:: Approaching the promises of easy configuration.
@end menu
@node Introduction, Distributing, Top, Top
If this macro finds @file{alloca.h}, it defines @code{HAVE_ALLOCA_H}.
-This macro does not try to get @code{alloca} from the SVR3 @file{libPW}
-or the SVR4 @file{libucb} because those libraries contain some
-incompatible functions that cause trouble. Some versions do not even
-contain @code{alloca} or contain a buggy version. If you still want to
-use their @code{alloca}, use @code{ar} to extract @file{alloca.o} from
-them instead of compiling @file{alloca.c}.
+This macro does not try to get @code{alloca} from the System V R3
+@file{libPW} or the System V R4 @file{libucb} because those libraries
+contain some incompatible functions that cause trouble. Some versions
+do not even contain @code{alloca} or contain a buggy version. If you
+still want to use their @code{alloca}, use @code{ar} to extract
+@file{alloca.o} from them instead of compiling @file{alloca.c}.
Source files that use @code{alloca} should start with a piece of code
like the following, to declare it properly. Note that in some versions
whether it found a match.
To check whether the Autoconf macros have already defined a certain C
-preprocessor symbol, you can use a @code{case} statement like this:
+preprocessor symbol, test the value of the appropriate cache variable,
+as in this example:
@example
-case "$DEFS" in
- *HAVE_FOO*) ;;
- *) LIBOBJS="$LIBOBJS foo.o" ;;
-esac
+AC_CHECK_FUNC(vprintf, AC_DEFINE(HAVE_VPRINTF))
+if test "$ac_cv_func_vprintf" != yes; then
+AC_CHECK_FUNC(_doprnt, AC_DEFINE(HAVE_DOPRNT))
+fi
@end example
@noindent
-Make sure to enclose the variable name you are checking (usually
-@code{DEFS}) in double quotes, because otherwise some old versions of
-@code{bash} misinterpret the statement.
+Unlike in Autoconf version 1, there is no shell variable @code{DEFS} set
+while @code{configure} is running. This difference is because properly
+quoting the contents of that variable turned out to be too cumbersome to
+do every time @code{AC_DEFINE} is called.
@node Test Programs, Multiple Cases, Checking for Symbols, Writing Macros
@section Test Programs
@code{AC_OS_DYNIX}
@end table
-@node Example, Preprocessor Symbol Index, Old Macro Names, Top
+@node Example, History, Old Macro Names, Top
@chapter An Example
Here are sample @file{configure.in} and @file{Makefile.in} files, to
CFLAGS = -g
LDFLAGS = -g
-prefix = /usr/local
-exec_prefix = $(prefix)
+prefix = @@prefix@@
+exec_prefix = @@exec_prefix@@
binprefix =
manprefix =
rm -rf `cat .fname` .fname
@end example
-@node Preprocessor Symbol Index, Macro Index, Example, Top
+@node History, Preprocessor Symbol Index, Example, Top
+@chapter History of Autoconf
+
+You may be wondering, Why was Autoconf originally written? How did it
+get into its present form? (Why does it look like gorilla spit?) If
+you're not wondering, then this chapter contains no information useful
+to you, and you might as well skip it. If you @emph{are} wondering,
+then let there be light.
+
+@menu
+* Genesis:: Prehistory and naming of @code{configure}.
+* Exodus:: The plagues of @code{m4} and Perl.
+* Leviticus:: The priestly code of portability arrives.
+* Numbers:: Listing of growth and contributors.
+* Deuteronomy:: Approaching the promises of easy configuration.
+@end menu
+
+@node Genesis, Exodus, , History
+@section Genesis
+
+In June 1991 I was maintaining many of the GNU utilities for the Free
+Software Foundation. As they were ported to more platforms and more
+programs were added, the number of @samp{-D} options that users had to
+select in the @file{Makefile} (around 20) became burdensome. Especially
+for me---I had to test each new release on a bunch of different systems.
+So I wrote a little shell script to guess some of the correct settings
+for the fileutils package, and released it as part of fileutils 2.0.
+That @code{configure} script worked well enough that the next month I
+adapted it (by hand) to create similar @code{configure} scripts for
+several other GNU utilities packages. Brian Berliner also adapted one
+of my scripts for his CVS revision control system.
+
+Later that summer, I learned that Richard Stallman and Richard Pixley
+were developing similar scripts to use in the GNU compiler tools; so I
+adapted my @code{configure} scripts to support their evolving interface:
+using the file name @file{Makefile.in} as the templates; adding
+@samp{+srcdir}, the first option (of many); and creating
+@file{config.status} files.
+
+@node Exodus, Leviticus, Genesis, History
+@section Exodus
+
+As I got feedback from users, I incorporated many improvements, using
+Emacs to search and replace, cut and paste, similar changes in each of
+the scripts. As I adapted more GNU utilities packages to use
+@code{configure} scripts, updating them all by hand became burdensome.
+Rich Murphey, the maintainer of the GNU graphics utilities, sent me mail
+saying that the @code{configure} scripts were great, and asking if I had
+a program for generating them that I could send him. No, I thought, but
+I should! So I started to work out how to generate them. And the
+journey from the bondage of hand-written @file{configure} scripts to the
+promise of Autoconf began.
+
+I looked briefly into using Larry Wall's Metaconfig program, but I
+decided not to for several reasons. The @code{Configure} scripts it
+produces are interactive, which I find quite inconvenient; I didn't like
+the ways it checked for some features (such as library functions); it
+was not being maintained, and its scripts didn't work on many modern
+systems (such as System V R4 and NeXT); it wasn't very flexible in what
+it could do in response to a feature's presence or absence; I found it
+confusing to learn; and it was too big and complex for my needs (I
+didn't realize then how much Autoconf would eventually have to grow). I
+considered using Perl to generate my style of @code{configure} scripts,
+but decided that @code{m4} was better suited to the job of simple
+textual substitutions: it gets in the way less, because output is
+implicit. Plus, everyone already has it. (Initially I didn't rely on
+the GNU extensions to @code{m4}.) Also, some of my friends at the
+University of Maryland had recently been putting @code{m4} front ends on
+several programs, including @code{tvtwm}, and I was interested in trying
+out a new language.
+
+@node Leviticus, Numbers, Exodus, History
+@section Leviticus
+
+Since my @code{configure} scripts determine the system's capabilities
+automatically, with no interactive user intervention, I decided to call
+the program that generates them Autoconfig. But with a version number
+tacked on, that name would be too long for System V R3 file systems, so
+I shortened it to Autoconf.
+
+I called together a group of priests of portability (er, alpha testers)
+to give me feedback as I encapsulated pieces of my handwritten scripts
+in @code{m4} macros and continued to add features and improve the
+techniques used in the checks. Prominent among the testers were
+@ifinfo
+Franc,ois
+@end ifinfo
+@tex
+Fran\c cois
+@end tex
+Pinard, who came up with the idea of making an @file{autoconf} shell
+script to run @code{m4} and check for unresolved macro calls; Karl
+Berry, who championed standardizing the @code{HAVE_@var{feature}} form
+for C preprocessor symbols; and Ian Taylor, who added support for
+creating a C header file as an alternative to putting @samp{-D} options
+in a @file{Makefile}, so he could use it in his UUCP package. The alpha
+testers cheerfully adjusted their files again and again as the names and
+calling conventions of the Autoconf macros changed from release to
+release. They all contributed many specific checks, great ideas, and
+bug fixes.
+
+@node Numbers, Deuteronomy, Leviticus, History
+@section Numbers
+
+In July 1992, after months of alpha testing, I released Autoconf 1.0,
+and converted many of GNU packages to use it. I was surprised by how
+positive the reaction to it was. More people started using it than I
+could keep track of, including people working on software that wasn't
+part of the GNU Project (such as TCL, FSP, @TeX{}, and Kerberos v5).
+Autoconf continued to improve rapidly, as many people using the
+@code{configure} scripts reported problems they encountered.
+
+Autoconf turned out to be a good torture test for @code{m4}
+implementations. Unix @code{m4} started to dump core because of the
+length of the macros that Autoconf defined, and several bugs showed up
+in GNU @code{m4} as well. Eventually, we realized that we needed to use
+some features that only GNU @code{m4} has. BSD @code{m4}, in
+particular, has an impoverished set of builtin macros; the System V
+version is better, but still doesn't have everything we need.
+
+More development occurred as people put Autoconf under more stresses
+(and to uses I'd never imagined). Karl Berry added checks for X11.
+david zuhn contributed C++ support.
+@ifinfo
+Franc,ois
+@end ifinfo
+@tex
+Fran\c cois
+@end tex
+Pinard made it diagnose invalid arguments. Jim Blandy bravely coerced
+it into configuring GNU Emacs, laying the groundwork for several later
+improvements. Roland McGrath got it to configure the GNU C Library,
+wrote the @code{autoheader} script to automate the creation of C header
+file templates, and added a @samp{--verbose} option to @code{configure}.
+Noah Friedman added the @samp{--macrodir} option and @code{AC_MACRODIR}
+environment variable. Roland and Noah improved the quoting protection
+in @code{AC_DEFINE} and fixed many bugs, especially when I got sick of
+dealing with portability problems from February through June, 1993.
+
+@node Deuteronomy, , Numbers, History
+@section Deuteronomy
+
+A long wish list for major features had accumulated, and the effect of
+several years of patching by various people had left some residual
+cruft. In April 1994, while working for Cygnus Support, I began a major
+revision of Autoconf. I added most of the features of the Cygnus
+@code{configure} that Autoconf had lacked; for example, support for
+using @file{config.sub} and options like @samp{--host}, derived from
+work that david zuhn and Ken Raeburn contributed while converting GNU
+@code{as} to use Autoconf. Rob Savoye required the ability to run
+@code{configure} scripts in subdirectories when he made DejaGNU use
+Autoconf.
+
+I added more features in response to other peoples' requests. Many
+people had asked for @code{configure} scripts to share the results of
+the checks between runs, because (particularly when configuring a large
+source tree, like Cygnus does) they were frustratingly slow. Mike
+Haertel suggested adding site-specific initialization scripts. People
+distributing software that had to unpack on MS-DOS asked for a way to
+override the @file{.in} extension on the file names. Jim Avera did an
+extensive examination of the problems with quoting in @code{AC_DEFINE}
+and contributed significant improvements to it. Richard Stallman asked
+that compiler output be sent to @file{config.log} instead of
+@file{/dev/null}, to help people debug the Emacs @code{configure}
+script.
+
+I made some other changes because of my dissatisfaction with the quality
+of the program. I made the messages showing results of the checks less
+ambiguous, always printing a result. I regularized the names of the
+macros and cleaned up coding style inconsistencies. I added several
+useful auxiliary utilities that I had developed to help convert source
+code packages to use Autoconf. And I began a testsuite, because
+experience had shown that Autoconf had a pronounced tendency to regress
+when we changed it.
+
+Again, several alpha testers gave invaluable feedback, especially
+@ifinfo
+Franc,ois
+@end ifinfo
+@tex
+Fran\c cois
+@end tex
+Pinard, Rob Savoye, and Ken Raeburn.
+
+Finally, version 2.0 was ready.
+
+@node Preprocessor Symbol Index, Macro Index, History, Top
@unnumbered Preprocessor Symbol Index
This is an alphabetical list of the C preprocessor symbols that the
dnl
AC_DEFUN(AC_PATH_X,
[AC_REQUIRE_CPP()dnl Set CPP; we run AC_PATH_X_DIRECT conditionally.
-# If we find X, set shell vars x_includes and x_libraries to the paths.
-no_x=yes
-if test "x$with_x" != xno; then
+# If we find X, set shell vars x_includes and x_libraries to the
+# paths, otherwise set no_x=yes.
+# Uses ac_ vars as temps to allow command line to override cache and checks.
+# --without-x overrides everything else, but does not touch the cache.
+AC_MSG_CHECKING(for X)
-# Command line options override cache.
-# FIXME We need to allow --x=includes= to work, I think.
-test -n "$x_includes" && ac_cv_x_includes="$x_includes"
-test -n "$x_libraries" && ac_cv_x_includes="$x_libraries"
-if test "${ac_cv_x_includes+set}" = set &&
- test "${ac_cv_x_libraries+set}" = set; then
- AC_VERBOSE(using cached values for ac_cv_x_includes and ac_cv_x_libraries)
+if test "x$with_x" = xno; then
+ no_x=yes
else
+ if test "x$x_includes" != xNONE && test "x$x_libraries" != xNONE; then
+ no_x=
+ else
+AC_CACHE_VAL(ac_cv_path_x,
+[# One or both of the vars are not set, and there is no cached value.
+no_x=yes
AC_PATH_X_XMKMF
-fi
-if test "${ac_cv_x_includes+set}" != set ||
- test "${ac_cv_x_libraries+set}" != set; then
+if test "$no_x" = yes; then
AC_PATH_X_DIRECT
fi
-test -z "$ac_cv_x_includes" && ac_cv_x_includes=NONE
-test -z "$ac_cv_x_libraries" && ac_cv_x_libraries=NONE
+if test "$no_x" = yes; then
+ ac_cv_path_x="no_x=yes"
+else
+ ac_cv_path_x="no_x= ac_x_includes=$ac_x_includes ac_x_libraries=$ac_x_libraries"
+fi])dnl
+ fi
+ eval "$ac_cv_path_x"
+fi # $with_x != no
-# FIXME can we reliably distinguish cache values that are set to empty
-# from those that aren't set?
-if test -z "$x_includes" && test "$ac_cv_x_includes" != NONE; then
- x_includes="$ac_cv_x_includes"
-fi
-if test -z "$x_libraries" && test "$ac_cv_x_libraries" != NONE; then
- x_libraries="$ac_cv_x_libraries"
+if test "$no_x" = yes; then
+ AC_MSG_RESULT(no)
+else
+ test "x$x_includes" = xNONE && x_includes=$ac_x_includes
+ test "x$x_libraries" = xNONE && x_libraries=$ac_x_libraries
+ ac_cv_path_x="no_x= ac_x_includes=$x_includes ac_x_libraries=$x_libraries"
+ AC_MSG_RESULT([libraries $x_libraries, headers $x_includes])
fi
-
-test -n "$x_includes" && AC_VERBOSE(X11 headers are in $x_includes)
-test -n "$x_libraries" && AC_VERBOSE(X11 libraries are in $x_libraries)
-fi # No --with-x=no.
])dnl
dnl
dnl Internal subroutine of AC_PATH_X.
+dnl Set ac_x_includes, ac_x_libraries, and no_x (initially yes).
AC_DEFUN(AC_PATH_X_XMKMF,
-[AC_CHECKING(for X include and library files with xmkmf)
-rm -fr conftestdir
+[rm -fr conftestdir
if mkdir conftestdir; then
cd conftestdir
# Make sure to not put "make" in the Imakefile rules, since we grep it out.
fi
case "$ac_im_incroot" in
/usr/include) ;;
- *) test -z "$ac_cv_x_includes" && ac_cv_x_includes="$ac_im_incroot" ;;
+ *) ac_x_includes="$ac_im_incroot" ;;
esac
case "$ac_im_usrlibdir" in
/usr/lib | /lib) ;;
- *) test -z "$ac_cv_x_libraries" && ac_cv_x_libraries="$ac_im_usrlibdir" ;;
+ *) ac_x_libraries="$ac_im_usrlibdir" ;;
esac
fi
cd ..
])dnl
dnl
dnl Internal subroutine of AC_PATH_X.
+dnl Set ac_x_includes, ac_x_libraries, and no_x (initially yes).
AC_DEFUN(AC_PATH_X_DIRECT,
-[AC_CHECKING(for X include and library files directly)
-test -z "$x_direct_test_library" && x_direct_test_library=Xt
+[test -z "$x_direct_test_library" && x_direct_test_library=Xt
test -z "$x_direct_test_include" && x_direct_test_include=X11/Intrinsic.h
-AC_TRY_CPP([#include <$x_direct_test_include>], no_x=,
- for ac_dir in \
+AC_TRY_CPP([#include <$x_direct_test_include>], [no_x= ac_x_includes=],
+[ for ac_dir in \
/usr/X11R6/include \
/usr/X11R5/include \
/usr/X11R4/include \
; \
do
if test -r "$ac_dir/$x_direct_test_include"; then
- test -z "$ac_cv_x_includes" && ac_cv_x_includes=$ac_dir
- no_x=
+ no_x= ac_x_includes=$ac_dir
break
fi
- done)
+ done])
# Check for the libraries. First see if replacing the include by
# lib works.
-AC_HAVE_LIBRARY("$x_direct_test_library", no_x=,
-for ac_dir in `echo "$ac_cv_x_includes" | sed s/include/lib/` \
+AC_CHECK_LIB("$x_direct_test_library", main, [no_x= ac_x_libraries=],
+[for ac_dir in `echo "$ac_x_includes" | sed s/include/lib/` \
/usr/X11R6/lib \
/usr/X11R5/lib \
/usr/X11R4/lib \
do
for ac_extension in a so sl; do
if test -r $ac_dir/lib${x_direct_test_library}.$ac_extension; then
- test -z "$ac_cv_x_libraries" && ac_cv_x_libraries=$ac_dir
- no_x=
+ no_x= ac_x_libraries=$ac_dir
break 2
fi
done
-done)])dnl
+done])])dnl
dnl
dnl Find additional X libraries, magic flags, etc.
AC_DEFUN(AC_PATH_XTRA,
[AC_REQUIRE([AC_OS_ISC])dnl
AC_REQUIRE([AC_PATH_X])dnl
AC_CHECKING(for additional X libraries and flags)
-if test -n "$x_includes"; then
- X_CFLAGS="$X_CFLAGS -I$x_includes"
-elif test "$no_x" = yes; then
+if test "$no_x" = yes; then
# Not all programs may use this symbol, but it does not hurt to define it.
X_CFLAGS="$X_CFLAGS -DX_DISPLAY_MISSING"
-fi
+else
+ if test -n "$x_includes"; then
+ X_CFLAGS="$X_CFLAGS -I$x_includes"
+ fi
-# It would be nice to have a more robust check for the -R ld option than
-# just checking for Solaris.
-# It would also be nice to do this for all -L options, not just this one.
-if test -n "$x_libraries"; then
- X_LIBS="$X_LIBS -L$x_libraries"
- if test "`(uname) 2>/dev/null`" = SunOS &&
- uname -r | grep '^5' >/dev/null; then
- X_LIBS="$X_LIBS -R$x_libraries"
+ # It would be nice to have a more robust check for the -R ld option than
+ # just checking for Solaris.
+ # It would also be nice to do this for all -L options, not just this one.
+ if test -n "$x_libraries"; then
+ X_LIBS="$X_LIBS -L$x_libraries"
+ if test "`(uname) 2>/dev/null`" = SunOS &&
+ uname -r | grep '^5' >/dev/null; then
+ X_LIBS="$X_LIBS -R$x_libraries"
+ fi
fi
-fi
-# Check for additional X libraries.
+ # Check for additional X libraries.
-if test "$ISC" = yes; then
- X_EXTRA_LIBS="$X_EXTRA_LIBS -lnsl_s -linet"
-else
- # Martyn.Johnson@cl.cam.ac.uk says this is needed for Ultrix, if the X
- # libraries were built with DECnet support. And karl@cs.umb.edu says
- # the Alpha needs dnet_stub (dnet does not exist).
- AC_CHECK_LIB(dnet, dnet_ntoa,
- [X_EXTRA_LIBS="$X_EXTRA_LIBS -ldnet" ac_have_dnet=yes], ac_have_dnet=no)
- if test "$ac_have_dnet" = no; then
- AC_CHECK_LIB(dnet_stub, dnet_ntoa,
- [X_EXTRA_LIBS="$X_EXTRA_LIBS -ldnet_stub"])
- fi
- # lieder@skyler.mavd.honeywell.com says without -lsocket,
- # socket/setsockopt and other routines are undefined under SCO ODT 2.0.
- # But -lsocket is broken on IRIX, according to simon@lia.di.epfl.ch.
- if test "`(uname) 2>/dev/null`" != IRIX; then
- AC_CHECK_LIB(socket, socket, [X_EXTRA_LIBS="$X_EXTRA_LIBS -lsocket"])
+ if test "$ISC" = yes; then
+ X_EXTRA_LIBS="$X_EXTRA_LIBS -lnsl_s -linet"
+ else
+ # Martyn.Johnson@cl.cam.ac.uk says this is needed for Ultrix, if the X
+ # libraries were built with DECnet support. And karl@cs.umb.edu says
+ # the Alpha needs dnet_stub (dnet does not exist).
+ AC_CHECK_LIB(dnet, dnet_ntoa,
+ [X_EXTRA_LIBS="$X_EXTRA_LIBS -ldnet" ac_have_dnet=yes], ac_have_dnet=no)
+ if test "$ac_have_dnet" = no; then
+ AC_CHECK_LIB(dnet_stub, dnet_ntoa,
+ [X_EXTRA_LIBS="$X_EXTRA_LIBS -ldnet_stub"])
+ fi
+ # lieder@skyler.mavd.honeywell.com says without -lsocket,
+ # socket/setsockopt and other routines are undefined under SCO ODT 2.0.
+ # But -lsocket is broken on IRIX, according to simon@lia.di.epfl.ch.
+ if test "`(uname) 2>/dev/null`" != IRIX; then
+ AC_CHECK_LIB(socket, socket, [X_EXTRA_LIBS="$X_EXTRA_LIBS -lsocket"])
+ fi
fi
fi
-#
-AC_VERBOSE(X compiler flags: $X_CFLAGS)
-AC_VERBOSE(X library flags: $X_LIBS)
-AC_VERBOSE(extra X libraries: $X_EXTRA_LIBS)
AC_SUBST(X_CFLAGS)dnl
AC_SUBST(X_LIBS)dnl
AC_SUBST(X_EXTRA_LIBS)dnl
projects / thirdparty / autoconf.git / commitdiff
