C API

Warning

The C API is intended for developers of other libraries. Special carre needs to be taken for correct memory management.

Note

When working with libcaosdb’s C API keep the following in mind:

Delete all objects (transactions, entities, properties, parents, …) that you created using a call to caosdb_..._create_... or released using caosdb_..._release_... and only those.

Specifically, any objects set by a caosdb_..._get_... function are managed by another owning object (e.g., a connection object is managed by the connection manager) and thus should not be deleted manually.

The underlying reason is that all C++ objects are realized in the Extern C interface as mutable structs containing a void pointer to the actuall C++ object which is not filled when initializing the struct but after calling a create function instead. If the C++ object wasn’t created using a create function, e.g., the parent object when getting a parent of an entity, it is owned by another object and deleted together with that object.