centos7下python3安装

centos7下python3安装

1.下载安装包

将安装包下载到 /usr/local目录下

wget -i -c  https://www.python.org/ftp/python/3.9.7/Python-3.9.7.tgz

2.解压

tar –zxvf Python-3.9.7.tgz

3.安装python的yum依赖

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

4.进入解压后的目录，依次执行，其中--prefix是Python的安装目录

./configure --prefix=/usr/local/python3
make
make install

5.配置环境变量

修改/etc/profile，在文件末位添加

export PYTHON_HOME=/usr/local/python3
export PATH=$PATH:$PYTHON_HOME/bin

6.检查是否安装成功

python

7.切换python版本

如果系统默认带了python，想切换成刚刚安装的版本，通过软链的方式解决

进入到目录cd /usr/bin

查看python指向

 发现python指向了python2,

备份原软链

mv /usr/bin/python /usr/bin/python.bak
mv /usr/bin/pip /usr/bin/pip.bak

创建新软链

ln -s /usr/local/python3/bin/python3.9 /usr/bin/python
ln -s /usr/local/python3/bin/pip3.9 /usr/bin/pip

8.检查是否切换成功

python

9.因为yum不支持python3，需要把yum默认的python执行改成python2

vim /usr/bin/yum

 vim /usr/libexec/urlgrabber-ext-down

将#!/usr/bin/python 改成#!/usr/bin/python2

10.检查yum是否OK

yum list|grep mysql