socket_cmsg_space Calculate message buffer size &reftitle.description; intnullsocket_cmsg_space intlevel inttype intnum0 Calculates the size of the buffer that should be allocated for receiving the ancillary data. &warn.undocumented.func; &reftitle.parameters; level type &reftitle.returnvalues; &reftitle.seealso; socket_recvmsg socket_sendmsg