【Python 开发】第二篇 ：Python安装

一、python3.x安装

1）由于centos7原本就安装了Python2，而且这个Python2不能被删除，因为有很多系统命令，比如yum都要用到。

官网：https://www.python.org/

[root@host130 ~]# python
Python 2.7.5 (default, Nov  6 2016, 00:28:07) 
[GCC 4.8.5 20150623 (Red Hat 4.8.5-11)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()
[root@host130 ~]# which python
/usr/bin/python
[root@host130 ~]# 

二、源码安装python3.7　　

2）通过源码安装python3.x，我选择是安装python3.7
2.1 下载依赖包
[root@host130 ~]# yum -y install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gdbm-devel db4-devel libpcap-devel xz-devel libffi-devel2.2 

[root@host130 src]# pwd 
/usr/local/src 

下载不同版本的Python3，我下载的是Python3.7

[root@host130 src]# wget https://www.python.org/ftp/python/3.7.0/Python-3.7.0rc1.tgz 
[root@host130 src]# tar -zxvf Python-3.7.0rc1.tgz
[root@host130 src]# cd Python-3.7.0rc1/ 
[root@host130 Python-3.7.0rc1]# ls 
aclocal.m4 configure.ac install-sh
Mac Objects Programs setup.py config.guess Doc Lib Makefile.pre.in Parser pyconfig.h.in 
Tools config.sub Grammar LICENSE Misc PC Python configure Include m4 Modules PCbuild README.rst 
[root@host130 Python-3.7.0rc1]# ./config 
config.guess config.sub configure 
[root@host130 Python-3.7.0rc1]# ./configure --prefix=/usr/local/python3 
[root@host130 Python-3.7.0rc1]# make && make install

[root@host130 Python-3.7.0rc1]# ln -s /usr/local/python3/bin/python3 /usr/bin/python3
[root@host130 Python-3.7.0rc1]# ln -s /usr/local/python3/bin/pip3 /usr/bin/pip3
[root@host130 Python-3.7.0rc1]# python3
Python 3.7.0rc1 (default, Sep 18 2018, 18:22:18) 
[GCC 4.8.5 20150623 (Red Hat 4.8.5-11)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> exit
Use exit() or Ctrl-D (i.e. EOF) to exit
>>> 

参考博客：https://www.cnblogs.com/dangkai/p/9394363.html

三、编译时报错处理

o module named '_ctypes'    参考博客：https://blog.csdn.net/qq_36416904/article/details/79316972

的解决办法：
原因：3.7版本需要一个新的包libffi-devel，安装此包之后再次进行编译安装即可。
[root@host130 Python-3.7.0rc1]# yum -y install libffi-devel
[root@host130 Python-3.7.0rc1]# make && make install
安装成功：
[root@host130 Python-3.7.0rc1]# ln -s /usr/local/python3/bin/python3 /usr/bin/python3
[root@host130 Python-3.7.0rc1]# ln -s /usr/local/python3/bin/pip3 /usr/bin/pip3
[root@host130 Python-3.7.0rc1]# python3
Python 3.7.0rc1 (default, Sep 18 2018, 18:22:18) 
[GCC 4.8.5 20150623 (Red Hat 4.8.5-11)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> exit
Use exit() or Ctrl-D (i.e. EOF) to exit
>>>