CentOS6.5下autoconf源码安装升级到autoconf2.68版本

在安装 PHP7.3.21 Redis 扩展时，提示当前autoconf版本是2.63要升级到2.68及以上版本

查询当前版本：

1 2	[root@localhost ~]# rpm -qa \| grep autoconf autoconf-2.63-5.1.el6.noarch

或

1	[root@localhost ~]# rpm -qf /usr/bin/autoconf

卸载当前版本：

1	[root@localhost ~]# rpm -e --nodeps autoconf-2.63

安装最新版本：

[root@localhost ~]# cd /usr/local/src
[root@localhost src]# wget ftp://ftp.gnu.org/gnu/autoconf/autoconf-2.68.tar.gz 
[root@localhost src]# tar -zxvf autoconf-2.68.tar.gz 
[root@localhost src]# cd autoconf-2.68 
[root@localhost autoconf-2.68]# ./configure --prefix=/usr/ 
[root@localhost autoconf-2.68]# make && make install

查看当前版本：

[root@localhost autoconf-2.68]# /usr/bin/autoconf -V
autoconf (GNU Autoconf) 2.68
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+/Autoconf: GNU GPL version 3 or later
<http://gnu.org/licenses/gpl.html>, <http://gnu.org/licenses/exceptions.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by David J. MacKenzie and Akim Demaille.

autoconf已升级到2.68了(^▽^)！