|
|
1.1 root 1: .\" Copyright (c) 1983 The Regents of the University of California.
2: .\" All rights reserved.
3: .\"
4: .\" Redistribution and use in source and binary forms are permitted provided
5: .\" that: (1) source distributions retain this entire copyright notice and
6: .\" comment, and (2) distributions including binaries display the following
7: .\" acknowledgement: ``This product includes software developed by the
8: .\" University of California, Berkeley and its contributors'' in the
9: .\" documentation or other materials provided with the distribution and in
10: .\" all advertising materials mentioning features or use of this software.
11: .\" Neither the name of the University nor the names of its contributors may
12: .\" be used to endorse or promote products derived from this software without
13: .\" specific prior written permission.
14: .\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
15: .\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
16: .\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
17: .\"
18: .\" @(#)inet.4 6.5 (Berkeley) 6/23/90
19: .\"
20: .TH INET 4 "June 23, 1990"
21: .UC 5
22: .SH NAME
23: inet \- Internet protocol family
24: .SH SYNOPSIS
25: .B #include <sys/types.h>
26: .br
27: .B #include <netinet/in.h>
28: .SH DESCRIPTION
29: .de _d
30: .if t .ta .6i 2.1i 2.6i
31: .\" 2.94 went to 2.6, 3.64 to 3.30
32: .if n .ta .84i 2.6i 3.30i
33: ..
34: .de _f
35: .if t .ta .5i 1.25i 2.5i
36: .\" 3.5i went to 3.8i
37: .if n .ta .7i 1.75i 3.8i
38: ..
39: The Internet protocol family is a collection of protocols
40: layered atop the
41: .I Internet Protocol
42: (IP) transport layer, and utilizing the Internet address format.
43: The Internet family provides protocol support for the
44: SOCK_STREAM, SOCK_DGRAM, and SOCK_RAW socket types; the
45: SOCK_RAW interface provides access to the IP protocol.
46: .SH ADDRESSING
47: Internet addresses are four byte quantities, stored in
48: network standard format (on the VAX these are word and byte
49: reversed). The include file
50: .RI < netinet/in.h >
51: defines this address
52: as a discriminated union.
53: .PP
54: Sockets bound to the Internet protocol family utilize
55: the following addressing structure,
56: .sp 1
57: .nf
58: ._f
59: struct sockaddr_in {
60: short sin_family;
61: u_short sin_port;
62: struct in_addr sin_addr;
63: char sin_zero[8];
64: };
65: .sp 1
66: .fi
67: Sockets may be created with the local address INADDR_ANY
68: to effect \*(lqwildcard\*(rq matching on incoming messages.
69: The address in a
70: .IR connect (2)
71: or
72: .IR sendto (2)
73: call may be given as INADDR_ANY to mean ``this host.''
74: The distinguished address INADDR_BROADCAST
75: is allowed as a shorthand for the broadcast address on the primary
76: network if the first network configured supports broadcast.
77: .SH PROTOCOLS
78: The Internet protocol family is comprised of
79: the IP transport protocol, Internet Control
80: Message Protocol (ICMP), Transmission Control
81: Protocol (TCP), and User Datagram Protocol (UDP).
82: TCP is used to support the SOCK_STREAM
83: abstraction while UDP is used to support the SOCK_DGRAM
84: abstraction. A raw interface to IP is available
85: by creating an Internet socket of type SOCK_RAW.
86: The ICMP message protocol is accessible from a raw socket.
87: .PP
88: The 32-bit Internet address contains both network and host parts.
89: It is frequency-encoded; the most-significant bit is clear
90: in Class A addresses, in which the high-order 8 bits are the network
91: number.
92: Class B addresses use the high-order 16 bits as the network field,
93: and Class C addresses have a 24-bit network part.
94: Sites with a cluster of local networks and a connection to the DARPA
95: Internet may chose to use a single network number for the cluster;
96: this is done by using subnet addressing.
97: The local (host) portion of the address is further subdivided
98: into subnet and host parts.
99: Within a subnet, each subnet appears to be an individual network;
100: externally, the entire cluster appears to be a single, uniform
101: network requiring only a single routing entry.
102: Subnet addressing is enabled and examined by the following
103: .IR ioctl (2)
104: commands on a datagram socket in the Internet domain;
105: they have the same form as the
106: SIOCIFADDR command (see
107: .IR intro (4)).
108: .PP
109: .TP 20
110: SIOCSIFNETMASK
111: Set interface network mask.
112: The network mask defines the network part of the address;
113: if it contains more of the address than the address type would indicate,
114: then subnets are in use.
115: .TP 20
116: SIOCGIFNETMASK
117: Get interface network mask.
118: .SH SEE ALSO
119: ioctl(2), socket(2), intro(4), tcp(4), udp(4), ip(4), icmp(4)
120: .PP
121: An Introductory 4.3BSD Interprocess Communication Tutorial (PS1:7).
122: .PP
123: An Advanced 4.3BSD Interprocess Communication Tutorial (PS1:8).
124: .SH CAVEAT
125: The Internet protocol support is subject to change as
126: the Internet protocols develop. Users should not depend
127: on details of the current implementation, but rather
128: the services exported.
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.