This command will reload the services configuration files from disk. Changes made to the configuration files are automatically applied to services and services behaviour will change accordingly in most cases. This provides a quieter way of updating services than using a restart. Unlike with modifying other configuration files, making configuration errors here will not cause an unintended shutdown of services. Instead, services will tell you where the configuration error lies. However, should services shut down in this state for any reason, then the errors will need to be fixed before services can be restarted. Therefore, you should fix any such errors immediately upon seeing them.
This command accepts 0 arguments. You can issue the command like this:
/msg OperServ rehash