CentOS 7: 解决"INSTALL mysqlclient.pc lib/pkgconfig" 问题，并安装 Doxygen

To resolve the missing Doxygen issue and install 'mysqlclient.pc lib/pkgconfig' on CentOS 7, you can follow these steps:

1. Install Doxygen:
   • Enable the EPEL repository if it is not already enabled:

sudo yum install epel-release ```

• Install Doxygen:

sudo yum install doxygen ```

2. Install MySQL client development package:
   • Enable the MySQL repository if it is not already enabled:

sudo yum install https://dev.mysql.com/get/mysql80-community-release-el7-3.noarch.rpm ```

• Install the MySQL client development package:

sudo yum install mysql-community-devel ```

3. Verify the installation:
   • Check if Doxygen is installed:

doxygen --version ```

• Check if the MySQL client development package is installed:

mysql_config --version ```

After following these steps, the missing Doxygen issue should be resolved, and 'mysqlclient.pc lib/pkgconfig' should be installed on your CentOS 7 system.