In general, when a Client-Library application sends a command to the server, it cannot send another command on the same connection until ct_results returns CS_END_RESULTS, CS_CANCELED, or CS_FAIL.
An exception to this rule occurs when ct_results returns cursor results. In this case, the application can:
Send a cursor command on the same command structure that is processing the cursor results. Applications commonly use this technique to perform cursor updates and deletes.
Send an unrelated command on any other command structure.