Function laminar_subscribe_callback 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn laminar_subscribe_callback(
    conn: *mut LaminarConnection,
    query: *const c_char,
    on_data: LaminarSubscriptionCallback,
    on_error: LaminarErrorCallback,
    user_data: *mut c_void,
    out: *mut *mut LaminarSubscriptionHandle,
) -> i32

Create a callback-based subscription.

The on_data callback is invoked from a background thread when new data arrives. The callback receives ownership of the batch and must free it.

Arguments

• conn - Database connection
• query - SQL query string (null-terminated)
• on_data - Callback for data batches (may be NULL to ignore data)
• on_error - Callback for errors (may be NULL to ignore errors)
• user_data - Opaque pointer passed to callbacks
• out - Pointer to receive subscription handle

Returns

LAMINAR_OK on success, or an error code.

Safety

• conn must be a valid connection handle
• query must be a valid null-terminated UTF-8 string
• out must be a valid pointer
• Callbacks must be thread-safe if user_data is shared