Centos7 python3安装

centos7 默认安装了python2

[[email protected] scripts]# python -V
Python 2.7.5

进入到/usr/bin目录，查看python文件

[[email protected] bin]# ll *python*
-rwxr-xr-x 1 root root 11312 Apr 27 22:53 abrt-action-analyze-python
lrwxrwxrwx 1 root root     7 Sep 11 08:37 python -> python2
lrwxrwxrwx 1 root root     9 Sep 11 08:37 python2 -> python2.7
-rwxr-xr-x 1 root root  7216 Jul 13 21:07 python2.7
-rwxr-xr-x 1 root root  1835 Jul 13 21:07 python2.7-config
lrwxrwxrwx 1 root root    16 Sep 11 08:37 python2-config -> python2.7-config
lrwxrwxrwx 1 root root    14 Sep 11 08:37 python-config -> python2-config

可以看到，python指向的是python2，python2指向的才是python2.7，所以实际上python2和python是一样的。

[[email protected] bin]# python2 -V
Python 2.7.5

下面使用源码安装python3
安装环境

yum install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gcc make

获取安装文件

wget https://www.python.org/ftp/python/3.6.2/Python-3.6.2.tar.xz

解压、安装

tar -xvJf  Python-3.6.2.tar.xz
cd Python-3.6.2
./configure prefix=/usr/local/python3
make && make install

添加指向python3的软连接

ln -s /usr/local/python3/bin/python3 /usr/bin/python3

查看python版本

[[email protected] Python-3.6.2]# python -V
Python 3.6.2
[[email protected] Python-3.6.2]# python2 -V
Python 2.7.5
[[email protected] Python-3.6.2]# python3 -V
Python 3.6.2