With this option, gem'll install mysql in /tmp directory.
Before run this, make sure u've install development tools like make,gcc, etc.
- root: gem install mysql -i /tmp/ruby-mysql/ -- --with-mysql-dir=/usr/local/mysql --with-mysql-lib=/usr/local/mysql/lib --with-mysql-include=/usr/local/mysql/include --with-mysql-config=/usr/local/mysql/bin/mysql_config
If u've problems after this installation, try to add
/usr/local/mysql/lib to /etc/ld.so.conf and run ldconfig.
This works fine for me.