The MariaDB Connector/C documentation notes that mysql_options is deprecated and will be removed at some point:
This function is deprecated as of MariaDB Connector/C 3.0 and will be removed in future releases. It's preferable to use mysql_optionsv.
It looks like mysql_options is still used quite a bit in C/ODBC in the MADB_DbcConnectDB function:
The replacement is mysql_optionsv: