centos安装python3,并与python2并存

1、环境查看
# echo $PATH    //查看bin目录的优先级
# which python  //查看python路径
# python -V     //查看版本，大写的V


2、准备环境
# yum install gcc c openssl-devel bzip2-devel expat-devel gdbm-devel readline-devel sqlite-devel wget -y
# wget https://www.python.org/ftp/python/2.7.13/Python-2.7.13.tgz
# wget https://www.python.org/ftp/python/3.6.2/Python-3.6.2.tgz
# mkdir /usr/local/{python3,python2}




3、安装
执行两次
# tar zxvf Python-*
# cd Python-*
# ./configure --prefix=/usr/local/python*
# make all
# make install
# make clean
# make distclean




4、配置bin目录
# ln -s /usr/local/python3/bin/python3 /usr/local/bin/python
# ln -s /usr/local/python3/bin/python3 /usr/local/bin/python3
# ln -s /usr/local/python3/bin/python3 /usr/local/bin/python3.6
# ln -s /usr/local/python3/bin/python3 /usr/local/bin/python3.6.2
# ln -s /usr/local/python2/bin/python /usr/local/bin/python2
# ln -s /usr/local/python2/bin/python /usr/local/bin/python2.7
# ln -s /usr/local/python2/bin/python /usr/local/bin/python2.7.13
退出shell重新打开
检测版本：
# python       -V
# python3      -V
# python3.6    -V
# python3.6.2  -V
# python2      -V
# python2.7    -V
# python2.7.13 -V


5、修改/usr/bin/yum
不用改了，因为yum调用的是/usr/bin/python,咱没有动他
# yum install unzip -y  //测试一下yum正常