Function duckdb_appender_error_data 

pub unsafe extern "C" fn duckdb_appender_error_data(
    appender: duckdb_appender,
) -> duckdb_error_data

Returns the error data associated with the appender. Must be destroyed with duckdb_destroy_error_data.

@param appender The appender to get the error data from. @return The error data.