/etc/logrotate.d/mysqld

mysqld

# cat /etc/logrotate.d/mysqld

# This logname can be set in /etc/my.cnf
# by setting the variable "err-log"
# in the [safe_mysqld] section as follows:
#
# [safe_mysqld]
# err-log=/var/log/mysqld.log
#
# If the root user has a password you have to create a
# /root/.my.cnf configuration file with the following
# content:
#
# [mysqladmin]
# password = <secret> 
# user= root
#
# where "<secret>" is the password. 
#
# ATTENTION: This /root/.my.cnf should be readable ONLY
# for Root !

# Then, un-comment the following lines to enable rotation of mysql's log file:

# /var/log/mysqld.log {
#         create 640 mysql mysql
#         notifempty
#     daily
#         rotate 3
#         missingok
#         compress
#     postrotate
#     # just if mysqld is really running
#     if test -x /usr/bin/mysqladmin && \
#         /usr/bin/mysqladmin ping &>/dev/null
#     then
#         /usr/bin/mysqladmin flush-logs
#     fi
#     endscript
# }

mysql_config_editor set --login-path=logrotate --host=localhost --socket=xxx --user=root --port 3306 --password
would be better, wouldn't it