Here are the data structures with brief descriptions:

cmdspec
cri_data	Command-Response Interleave: data for coordinating socket send (command) and receive (response) operations
evtlist_t
resplist_t
runcmd_data_t	Simple data structure and callback function for keeping track of asynchronous responses, for smoco_run_command() and its callback runcmd_cb()
SMOCO_Actuator	Represents a single stepper actuator
smoco_can_connect_t	Structure for specifying the details for connecting to the smocand daemon's CAN communication ports
SMOCO_CmdSpec	Fully specified command to SMOCO, comprising the command, node and actuator identifiers
SMOCO_Command	Detailed information about a SMOCO command
SMOCO_Data	Primary data structure for libsmoco
SMOCO_HANDLER_LI	Structure defining a response handler as a member ("list item") of a linked list
SMOCO_Node	Represents a single SMOCO controller and its positioning actuators
SMOCO_Parameters	A union type for specifying parameters to SMOCO commands
SMOCO_ParameterValue	A union for convenient access to the component bytes of a 32-bit SMOCO parameter
SMOCO_Response	Structure containing the details of a message received from the SMOCO hardware
SMOCO_ResponseUILabel
smoco_tx_t	Thread-local storage structure for libsmoco client threads
smocotx_t
txevent_t
txlist_t