root@wiki:~# which mysqld
/usr/sbin/mysqld
root@wiki:~# /usr/sbin/mysqld --verbose --help |grep -A 1 'Default options'
140712 3:09:08 [Warning] Using unique option prefix key_buffer instead of key_buffer_size is deprecated and will be removed in a future release. Please use the full name instead.
140712 3:09:08 [Warning] Using unique option prefix myisam-recover instead of myisam-recover-options is deprecated and will be removed in a future release. Please use the full name instead.
140712 3:09:08 [Note] Plugin 'FEDERATED' is disabled.
Default options are read from the following files in the given order:
/etc/my.cnf /etc/mysql/my.cnf /usr/etc/my.cnf ~/.my.cnf