# ulong readonly

#
# show the global and session values;
#
select @@global.extra_port;
--error ER_INCORRECT_GLOBAL_LOCAL_VAR
select @@session.extra_port;
show global variables like 'extra_port';
show session variables like 'extra_port';
select * from information_schema.global_variables where variable_name='extra_port';
select * from information_schema.session_variables where variable_name='extra_port';

#
# show that it's read-only
#
--error ER_INCORRECT_GLOBAL_LOCAL_VAR
set global extra_port=1;
--error ER_INCORRECT_GLOBAL_LOCAL_VAR
set session extra_port=1;