1.autoscan (autoconf): 扫描源代码以搜寻普通的可移植性问题，比如检查编译器，库，头文件等，生成文件configure.scan,它是configure.ac的一个雏形。
your source files --> [autoscan*] --> [configure.scan] --> configure.ac
2.aclocal (automake):根据已经安装的宏，用户定义宏和acinclude.m4文件中的宏将configure.ac文件所需要的宏集中定义到文件 aclocal.m4中。aclocal是一个perl 脚本程序，它的定义是：“aclocal - create aclocal.m4 by scanning configure.ac”user input files optional input process output files ================ ============== ======= ============ acinclude.m4 - - - - -. V .-------, configure.ac ------------------------>|aclocal| {user macro files} ->| |------> aclocal.m4 `-------' 3.autoheader(autoconf): 根据configure.ac中的某些宏，比如cpp宏定义，运行m4，声称config.h.in user input files optional input process output files ================ ============== ======= ============ aclocal.m4 - - - - - - - . | V .----------, configure.ac ----------------------->|autoheader|----> autoconfig.h.in `----------' 4.automake: automake将Makefile.am中定义的结构建立Makefile.in，然后configure脚本将生成的Makefile.in文件转换 为Makefile。如果在configure.ac中定义了一些特殊的宏，比如AC_PROG_LIBTOOL，它会调用libtoolize，否则它 会自己产生config.guess和config.sub
user input files optional input processes output files ================ ============== ========= ============ .--------, | | - - -> COPYING | | - - -> INSTALL | |------> install-sh | |------> missing |automake|------> mkinstalldirs configure.ac ----------------------->| | Makefile.am ----------------------->| |------> Makefile.in | |------> stamp-h.in .---+ | - - -> config.guess | | | - - -> config.sub | `------+-' | | - - - -> config.guess |libtoolize| - - - -> config.sub | |--------> ltmain.sh | |--------> ltconfig `----------'
5.autoconf:将configure.ac中的宏展开，生成configure脚本。这个过程可能要用到aclocal.m4中定义的宏。
user input files optional input processes output files ================ ============== ========= ============ aclocal.m4 ,autoconfig.h.in - - - - - - -. V .--------, configure.ac ----------------------->|autoconf|------> configure
6. ./configure的过程
.-------------> [config.cache] configure* --------------------------+-------------> config.log | [config.h.in] -. v .--> [autoconfig.h] +-------> config.status* -+ Makefile.in ---' `--> Makefile
7. make过程
[autoconfig.h] -. +--> make* ---> 程序 Makefile ---'
.---------, config.site - - ->| | config.cache - - ->|configure| - - -> config.cache | +-, `-+-------' | | |----> config.status config.h.in ------->|config- |----> config.h Makefile.in ------->| .status|----> Makefile | |----> stamp-h | +--, .-+ | | | `------+--' | ltmain.sh ------->|ltconfig|-------> libtool | | | `-+------' | |config.guess| | config.sub | `------------'
.--------, Makefile ------>| | config.h ------>| make | {project sources} ---------------->| |--------> {project targets} .-+ +--, | `--------' | | libtool | | missing | | install-sh | |mkinstalldirs| `-------------' 实例：
在/hello/目录下创建一个hello.c文件，并编译运行它：#cd /hello/
(1) 编写源文件hello.c：
#include<stdio.h>
int main(int argc, char** argv){ printf("Hello, GNU!n");return 0;}[litao@vm0000131 hello]$ ll
total 4-rw-rw-r-- 1 litao litao 68 Aug 12 12:02 hello.c一、autoscan
[litao@vm0000131 hello]$ autoscan
autom4te: configure.ac: no such file or directoryautoscan: /usr/bin/autom4te failed with exit status: 1[litao@vm0000131 hello]$ lltotal 8-rw-rw-r-- 1 litao litao 0 Aug 12 12:03 autoscan.log-rw-rw-r-- 1 litao litao 457 Aug 12 12:03 configure.scan-rw-rw-r-- 1 litao litao 68 Aug 12 12:02 hello.c已经生成了configure.scan，autoscan.log文件
将configure.scan 修改为 configure.in，最后修改的内容如下：
[litao@vm0000131 hello]$ mv configure.scan configure.in [litao@vm0000131 hello]$ vim configure.in
# -*- Autoconf -*-# Process this file with autoconf to produce a configure script.AC_PREREQ(2.59)AC_INIT(FULL-PACKAGE-NAME, VERSION, BUG-REPORT-ADDRESS)AC_CONFIG_SRCDIR([hello.c])#AC_CONFIG_HEADER([config.h])AM_INIT_AUTOMAKE(hello, 1.0)# Checks for programs.AC_PROG_CC# Checks for libraries.# Checks for header files.# Checks for typedefs, structures, and compiler characteristics.# Checks for library functions.AC_OUTPUT(Makefile)
二、acloacl
[litao@vm0000131 hello]$ aclocal
生成 aclocal.m4 和 autom4te.cache (生成aclocal.m4的过程中涉及到configure.in)
[litao@vm0000131 hello]$ lltotal 44-rw-rw-r-- 1 litao litao 31120 Aug 12 12:08 aclocal.m4drwxr-xr-x 2 litao litao 4096 Aug 12 12:08 autom4te.cache-rw-rw-r-- 1 litao litao 0 Aug 12 12:03 autoscan.log-rw-rw-r-- 1 litao litao 496 Aug 12 12:08 configure.in-rw-rw-r-- 1 litao litao 68 Aug 12 12:02 hello.c
三、antoconf
[litao@vm0000131 hello]$ autoconf生成 configure (根据 configure.in, 和 aclocal.m4)
[litao@vm0000131 hello]$ lltotal 168-rw-rw-r-- 1 litao litao 31120 Aug 12 12:08 aclocal.m4drwxr-xr-x 2 litao litao 4096 Aug 12 12:11 autom4te.cache-rw-rw-r-- 1 litao litao 0 Aug 12 12:03 autoscan.log-rwxrwxr-x 1 litao litao 122297 Aug 12 12:11 configure-rw-rw-r-- 1 litao litao 496 Aug 12 12:08 configure.in-rw-rw-r-- 1 litao litao 68 Aug 12 12:02 hello.c四、编写Makefile.am：AUTOMAKE_OPTIONS= foreign
bin_PROGRAMS= hellohello_SOURCES= hello.c五、automake
生成 Makefile.in， depcomp， install-sh， 和 missing (根据 Makefile.am, 和 aclocal.m4)
[litao@vm0000131 hello]$ automake
configure.in: required file `./install-sh' not foundconfigure.in: required file `./missing' not foundMakefile.am: required file `./depcomp' not found[litao@vm0000131 hello]$ automake --add-missingconfigure.in: installing `./install-sh'configure.in: installing `./missing'Makefile.am: installing `./depcomp'[litao@vm0000131 hello]$ lltotal 192-rw-rw-r-- 1 litao litao 31120 Aug 12 12:08 aclocal.m4drwxr-xr-x 2 litao litao 4096 Aug 12 12:14 autom4te.cache-rw-rw-r-- 1 litao litao 0 Aug 12 12:03 autoscan.log-rwxrwxr-x 1 litao litao 122297 Aug 12 12:11 configure-rw-rw-r-- 1 litao litao 496 Aug 12 12:08 configure.inlrwxrwxrwx 1 litao litao 31 Aug 12 12:16 depcomp -> /usr/share/automake-1.9/depcomp-rw-rw-r-- 1 litao litao 68 Aug 12 12:02 hello.clrwxrwxrwx 1 litao litao 34 Aug 12 12:16 install-sh -> /usr/share/automake-1.9/install-sh-rw-rw-r-- 1 litao litao 69 Aug 12 12:15 Makefile.am-rw-rw-r-- 1 litao litao 16561 Aug 12 12:16 Makefile.inlrwxrwxrwx 1 litao litao 31 Aug 12 12:16 missing -> /usr/share/automake-1.9/missing六、configure
生成 Makefile， config.log， 和 config.status