经常忘记测试机上mysql的root密码，学着写个脚本处理下

如题,脚本如下：

#!/bin/bash
confile="/etc/my.cnf"
n_passwd="new password"
mysql_bin="/etc/init.d/mysqld"
client_bin="/usr/bin/mysql"
# Backup Config File
cp ${confile} ${confile}_bak
# skip grant
sed -i '/\[mysqld\]/ a skip-grant-tables' $confile
# restart mysqld
${mysql_bin} restart
if [ $? -ne 0 ]; then
        exit -1
fi
# connect mysql
${client_bin} <<EOF
  USE mysql;
  UPDATE user SET Password = password ( '${n_passwd}' ) WHERE User = 'root' ;
  flush privileges;
  exit
EOF
# restart
sed -i '/skip-grant-tables/d' $confile
${mysql_bin} restart
diff ${confile} ${confile}_bak >> /dev/null
if [ -$? -eq 0 ]; then
        rm -f ${confile}_bak
else
        echo "Warning: Mysql Config File ${confile} has been changed."
        echo "Keep Backup as ${confile}_bak."
fi