majiayu000 Callback + Context Pattern (C-Specific)
Pair function pointer with void * user data. Callback receives user data, enabling state access without globals. Universal C pattern for async/event handling.
ikigai Application
Streaming responses:
typedef void (*chunk_cb_t)(void *user_ctx, const char *data, size_t len);
res_t ik_llm_stream(ik_llm_client_t *client,
ik_message_t **msgs,
chunk_cb_t on_chunk,
void *user_ctx); // Passed to callback
Usage: REPL passes itself as context, callback updates scrollback.
Convention: Callback function pointer immediately followed by void * context parameter. Callback signature includes context as first param.
Benefit: Stateful callbacks without globals. Each caller provides own context.