Specifying Program Options Your MySQL connection id is 3 Server version: 8.0.25 Source distribution Type ’help;’ or ’\h’ for help. Type ’\c’ to clear the buffer. mysql>  SELECT CURRENT_USER(); +----------------+ | CURRENT_USER() | +----------------+ | jon@% | +----------------+ 1 row in set (0.00 sec) shell>  mysql --host 85.224.35.45 --user mysql: option ’--user’ requires an argument shell>  mysql --host --user jon ERROR 2005 (HY000): Unknown MySQL server host ’--user’ (1) shell>  mysqld_safe & [1] 11699 shell> 080112 12:53:40 mysqld_safe Logging to ’/usr/local/mysql/var/tonfisk.err’. 080112 12:53:40 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/var shell> shell>  mysqld_safe --log-error & [1] 11699 shell> 080112 12:53:40 mysqld_safe Logging to ’/usr/local/mysql/var/tonfisk.err’. 080112 12:53:40 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/var shell> shell>  mysqld_safe --log-error my-errors & [1] 31357 shell> 080111 22:53:31 mysqld_safe Logging to ’/usr/local/mysql/var/tonfisk.err’. 080111 22:53:32 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/var 080111 22:53:34 mysqld_safe mysqld from pid file /usr/local/mysql/var/tonfisk.pid ended [1]+ Done ./mysqld_safe --log-error my-errors 354 The result is the same, since  --log-error  is not followed by anything else on the command line, and it supplies its own default value. (The  &  character tells the operating system to run MySQL in the background; it is ignored by MySQL itself.) Now suppose that you wish to log errors to a file named  my- errors.err . You might try starting the server with  --log-error my-errors , but this does not have the intended effect, as shown here: After shutting down the server, restart it as follows: Options having default values always require an equal sign when assigning a value; failing to do so causes an error. For example, the MySQL server  --log-error  option has the default value host_name .err , where  host_name  is the name of the host on which MySQL is running. Assume that you are running MySQL on a computer whose host name is “tonfisk” , and consider the following invocation of  mysqld_safe : Because  mysql  assumes that any string following  --host  on the command line is a host name,  --host --user  is interpreted as  --host=--user , and the client attempts to connect to a MySQL server running on a host named “--user” . In this case,  mysql  was unable to find a value following the  --user  option because nothing came after it on the command line. However, if you omit the value for an option that is  not  the last option to be used, you obtain a different error that you may not be expecting: Omitting the required value for one of these option yields an error, such as the one shown here: