Ubuntu 16.04 升级 PHP 版本至 7.1

安装swoole扩展，怎么安装到7.0下去了，我本来编译的版本是7.19版本，但是没吃

升级步骤

$ sudo add-apt-repository ppa:ondrej/php
$ sudo apt-get update
$ sudo apt-get upgrade php

直接安装提示这个：

www@TinywanAliYun:~$ pecl install swoole
The program 'pecl' is currently not installed. To run 'pecl' please ask your administrator to install the package 'php-pear'

sudo apt-get install php-pear

错误提示：

PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/lib/php/20160303/xml.so' - /usr/lib/php//xml.so: cannot open shared object file: No such file or directory in Unknown on line
PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/lib/php/20160303/dom.so' - /usr/lib/php//dom.so: cannot open shared object file: No such file or directory in Unknown on line 

开始了

1、软连接

sudo ln -s /usr/local/php-7.1./bin/php /usr/bin/php

2、php7.1-dev

sudo apt search php7

sudo apt-get install php7.-dev