You can use the SQL administration API to remotely administer Informix through SQL statements. Many of the operations are the same ones that you can complete with command line utilities. The advantage of using the SQL administration API functions is that you can run them remotely from other database servers; whereas you must be directly connected to the database server on which to run command line utility commands. If you haven't used SQL administration API commands, look at the SQL administration API documentation and try using some of the commands!
The SQL administration API portal topic lists all SQL administration API function arguments, sorted by category, with links to information about the arguments. This portal topic is in the SQL Administration API chapter in the IBM Informix Administrator's Reference and in the "SQL administration API functions" section of the Version 11.50 Information Center: