The Meta structure should be included as the first member of a Buffer metadata structure.
The structure defines the API of the metadata and should be accessible to all elements using the metadata.
A metadata API is registered with api_type_register which takes a name for the metadata API and some tags associated with the metadata. With api_type_has_tag one can check if a certain metadata API contains a given tag.
Multiple implementations of a metadata API can be registered. To implement a metadata API, register should be used. This function takes all parameters needed to create, free and transform metadata along with the size of the metadata. The function returns a MetaInfo structure that contains the information for the implementation of the API.
A specific implementation can be retrieved by name with get_info.
See Buffer for how the metadata can be added, retrieved and removed from buffers.