layer(s): 3, 4, 8, 9 header file(s): z_msgtrans.h classes in this group: packet_o, deluxe_packet_o, bytesize_packet_o, pktbuff_o, msgtrans_axiom_o, msgtrans_sockaddr_o, socket_channel_o, msgtrans_socket_o, msgtrans_unixsocket_o, msgtrans_inetsocket_o, msgtrans_o, mt_iface_o support/internal classes: msgtrans_addr_o description.
Message transport refers to the act of moving a block of data (eg, bytes) from a fixed point to another fixed point. There are a lot of terms for this: networking, circuit-based routing, etc. The delivery mechanism for message packets can be implemented via shared memory, sockets, TLI, message queues, or third-party systems (such as MQ Series). There is a wide assortment of techniques and mediums to send and route messages. Given that this topic has spawned a large sub-industry in computer software, it may appear a little presumptious to state that the Z Directory has attempted to provide a simple little interface to handle the job. the Z Directory provides a technique for sending a message between different types of transportation mechanisms - it can conceivably be used to send, say, an e-mail address to a location in shared memory, or to a particular socket port. There is a labyrinth of classes structured to be flexible, able to accomodate an ever-expanding number of transport methods: