Here are the data structures with brief descriptions:

Ciio_buffer	An input or output buffer, used to read or write samples
Ciio_channel	Represents an input or output channel of a device
Ciio_context	Contains the representation of an IIO context
Ciio_context_info	The information related to a discovered context
Ciio_data_format	Contains the format of a data sample
Ciio_device	Represents a device in the IIO context