Technical Standard: Networking Services (XNS), Issue 5.2 Draft 2.0
Copyright © 1999 The Open Group
Use of Sockets over Internet Protocols based on IPv4
Support for sockets over Internet Protocols based on IPv4 is mandatory.
This Chapter gives the protocol-specific information that is relevant
to the use of sockets in connection with TCP, UDP and ICMP
over Version 4 of the Internet Protocol - IPv4.
is defined in
to identify the IPv4 Internet address family.
contains other definitions used in connection with IPv4 Internet
structure defined in
is large enough to accommodate a
and is aligned at an appropriate boundary so that pointers
to it can be cast as pointers to
structures and used to access the fields of those structures without
alignment problems. When a
structure is cast as a
field maps onto the