本文给大家聊聊brew link更换php版本失败问题，希望对需要的朋友有所帮助！
问题描述：
我透過 brew 安裝三種php版本
php 5.6 php 7.4 php 8.0
$ php -v
PHP 8.0.3 (cli) (built: Mar 4 2021 20:45:17) ( NTS )
Copyright (c) The PHP Group
Zend Engine v4.0.3, Copyright (c) Zend Technologies
with Zend OPcache v8.0.3, Copyright (c), by Zend Technologies停用8.0使用7.4
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$ brew unlink php@8.0 && brew link php@7.4 Unlinking /usr/local/Cellar/php/8.0.3... 0 symlinks removed. Linking /usr/local/Cellar/php@7.4/7.4.16... 264 symlinks created. $ php -v
還是一樣版本
我開新的終端機也是一樣8.0.3
PHP 8.0.3 (cli) (built: Mar 4 2021 20:45:17) ( NTS )
Copyright (c) The PHP Group
Zend Engine v4.0.3, Copyright (c) Zend Technologies
with Zend OPcache v8.0.3, Copyright (c), by Zend Technologies中規中矩操作了
這是哪裏有少設置了？
分析解决：
你可以尝试安装一个PHP选择器
brew update brew upgrade
参考文档
https://github.com/shivammathur/homebrew-php
安装指定php brew install shivammathur/php/php@7.3
链接php版本 brew link --overwrite --force php@7.3
如果出现报错
Warning: Already linked:To relink: brew unlink && brew link
执行
brew unlink php@7.3 brew link --overwrite --force php@7.3
重启服务
apache brew services restart httpd nginx brew services restart nginx
安装结果
To enable PHP in Apache add the following to httpd.conf and restart Apache:
LoadModule php7_module /usr/local/opt/php@7.0/lib/httpd/modules/libphp7.so
SetHandler application/x-httpd-php
Finally, check DirectoryIndex includes index.php
DirectoryIndex index.php index.html
The php.ini and php-fpm.ini file can be found in:
/usr/local/etc/php/7.0/
php@7.0 is keg-only, which means it was not symlinked into /usr/local,
because this is an alternate version of another formula.
If you need to have php@7.0 first in your PATH run:
echo 'export PATH="/usr/local/opt/php@7.0/bin:$PATH"' >> ~/.zshrc
echo 'export PATH="/usr/local/opt/php@7.0/sbin:$PATH"' >> ~/.zshrc
For compilers to find php@7.0 you may need to set:
export LDFLAGS="-L/usr/local/opt/php@7.0/lib"
export CPPFLAGS="-I/usr/local/opt/php@7.0/include"
To have launchd start shivammathur/php/php@7.0 now and restart at login:
brew services start shivammathur/php/php@7.0
Or, if you don't want/need a background service you can just run:
php-fpm欢迎讨论！
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