@brief Retrieve committed offsets for topics+partitions.
The \p offset field of each requested partition will either be set to
stored offset or to RD_KAFKA_OFFSET_INVALID in case there was no stored
offset for that partition.
@returns RD_KAFKA_RESP_ERR_NO_ERROR on success in which case the
\p offset or \p err field of each \p partitions' element is filled
in with the stored offset, or a partition specific error.
Else returns an error code.
@brief Retrieve committed offsets for topics+partitions.
The \p offset field of each requested partition will either be set to stored offset or to RD_KAFKA_OFFSET_INVALID in case there was no stored offset for that partition.
@returns RD_KAFKA_RESP_ERR_NO_ERROR on success in which case the \p offset or \p err field of each \p partitions' element is filled in with the stored offset, or a partition specific error. Else returns an error code.