HP 9000 Networking XTI Programmer's Guide

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XTI over TCP/UDP Networks
Summary of TCP/UDP Programming Differences
Summary of TCP/UDP Programming Differences
HP-UX 10.0 supports two Internet protocols over XTI:
• Transmission Control Protocol (TCP)
• Unit Data Protocol (UDP)
The transport provider names are /dev/inet_cots and /dev/inet_clts. You can
create the device files /dev/tcp and /dev/udp with the equivalent major and
minor numbers as net_cots and net_clts if you prefer these names.
XTI defines a protocol profile that classifies a transport protocol in terms of
several common characteristics.
TCP supports the following profile:
TCP Transport Profile
info->addr sizeof(struct sockaddr_in)
info->options 256 /* TCP/IP options */
info->tsdu 0 /* */
info->etsdu -1
info->connect -2
info->discon -2
info->servtype T_COTS_ORD
info->flags 0
(Where: -2 means unsupported, -1 means indefinite length.
0 also means the concept is unsupported: no elements of the
feature are supported.)
The transport profile is returned when you call t_open() or t_getinfo().
Basically, the above profile specifies that TCP supports the address structure
sockaddr_in in /usr/include/netinet/in.h. TCP or IP options passed with
t_optmgmt() can be up to 256 bytes. TCP does not pass packetized data
(Transport Service Data Units). Streams data (bytes) are delivered in-order
and in amounts governed by network bandwidth not how many bytes you
specify with each t_snd(). No data can be passed with a connect or
disconnect request. TCP supports orderly release of connections: the
commands t_sndrel() and t_rcvrel() are supported; and the commands
close() and t_close() release the connection orderly. An orderly release
means that data in transit is attempted to be delivered (see below). The zero
value for the flags field means that HP TCP returns an error when you call
t_snd() with no data. t_sndzero is unsupported.