The Regents of the University of California. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. Neither the name of the University nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
@(#)4.t 8.1 (Berkeley) 6/8/93
.nr H2 1 .ds RH "Address representation
\s+2Internal address representation\s0
Common to all portions of the system are two data structures. These structures are used to represent addresses and various data objects. Addresses, internally are described by the sockaddr structure, ._f struct sockaddr { short sa_family; /* data format identifier */ char sa_data[14]; /* address */ }; All addresses belong to one or more address families which define their format and interpretation. The sa_family field indicates the address family to which the address belongs, and the sa_data field contains the actual data value. The size of the data field, 14 bytes, was selected based on a study of current address formats.* Specific address formats use private structure definitions that define the format of the data field. The system interface supports larger address structures, although address-family-independent support facilities, for example routing and raw socket interfaces, provide only 14 bytes for address storage. Protocols that do not use those facilities (e.g, the current Unix domain) may use larger data areas. .FS * Later versions of the system may support variable length addresses. .FE