Python开发【初始篇】：Linux下安装Python3

Linux系统默认自带python2.6的版本，这个版本被系统很多程序所依赖，所以建议不要轻易删除，除非你能解决其他程序的依赖问题。如果使用最新的Python3需要进行编译安装源码包，这样就对系统默认的包没有任何影响。

1. [root@test-c2c-console01 ~]# cat /etc/redhat-release
2. CentOS release 6.6 (Final)
3. [root@test-c2c-console01 ~]# uname -a
4. Linux test-c2c-console01.bj 2.6.32-504.el6.x86_64 #1 SMP Wed Oct 15 04:27:16 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
5. [root@test-c2c-console01 ~]# python -V
6. Python 2.6.6

Python官网下载pthon3源码包，https://www.python.org/

选择自己需要的版本

选择源码包

下载到本地然后上传到linux或者复制下载链接直接通过wget下载

1. [root@test-c2c-console01 tools]# wget -q https://www.python.org/ftp/python/3.5.2/Python-3.5.2.tgz
2. [root@test-c2c-console01 tools]# ll Python-3.5.2.tgz
3. -rw-r--r-- 1 root root 20566643 Jun 26 2016 Python-3.5.2.tgz

解压并安装

1. [root@test-c2c-console01 tools]# tar xf Python-3.5.2.tgz
2. [root@test-c2c-console01 tools]# cd Python-3.5.2
3. [root@test-c2c-console01 Python-3.5.2]# ./configure --prefix=/application/Python-3.5.2/ #指定安装目录
4. [root@test-c2c-console01 Python-3.5.2]# make && make install

创建软连接

1. [root@test-c2c-console01 Python-3.5.2]# cd /application/
2. [root@test-c2c-console01 application]# ln -s Python-3.5.2/ Python3
3. [root@test-c2c-console01 application]# ll
4. total 4
5. lrwxrwxrwx 1 root root 13 Mar 1 09:08 Python3 -> Python-3.5.2/
6. drwxr-xr-x 6 root root 4096 Mar 1 09:03 Python-3.5.2

到此python3就安装好了，启动pyhon3。

1. [root@test-c2c-console01 application]# /application/Python3/bin/python3
2. Python 3.5.2 (default, Mar 1 2017, 09:02:01)
3. [GCC 4.4.7 20120313 (Red Hat 4.4.7-11)] on linux
4. Type "help", "copyright", "credits" or "license" for more information.
5. >>>

由于这样启动比较麻烦可以通过配置环境变量解决。

1. [root@test-c2c-console01 application]# vim /etc/profile # 文件末尾添加python3路径
2. PATH="/application/Python3/bin/:$PATH"
3. [root@test-c2c-console01 application]# source /etc/profile # 更新环境变量
4. [root@test-c2c-console01 application]# which python3
5. /application/Python3/bin/python3
6. [root@test-c2c-console01 application]# which python
7. /usr/bin/python
8. [root@test-c2c-console01 application]# python3 -V
9. Python 3.5.2
10. [root@test-c2c-console01 application]# python -V
11. Python 2.6.6

启动系统默认的python

1. [root@test-c2c-console01 application]# python
2. Python 2.6.6 (r266:84292, Aug 18 2016, 15:13:37)
3. [GCC 4.4.7 20120313 (Red Hat 4.4.7-17)] on linux2
4. Type "help", "copyright", "credits" or "license" for more information.
5. >>>

启动python3

1. [root@test-c2c-console01 application]# python3
2. Python 3.5.2 (default, Mar 1 2017, 09:02:01)
3. [GCC 4.4.7 20120313 (Red Hat 4.4.7-11)] on linux
4. Type "help", "copyright", "credits" or "license" for more information.
5. >>>