xref: /illumos-gate/usr/src/man/man3xnet/inet_addr.3xnet (revision 30165b7f6753bc3d48c52319bed7ec7b3ea36b3c)

Sun Microsystems, Inc. gratefully acknowledges The Open Group for
permission to reproduce portions of its copyrighted documentation.
Original documentation from The Open Group can be obtained online at
http://www.opengroup.org/bookstore/.

The Institute of Electrical and Electronics Engineers and The Open
Group, have given us permission to reprint portions of their
documentation.

In the following statement, the phrase ``this text'' refers to portions
of the system documentation.

Portions of this text are reprinted and reproduced in electronic form
in the SunOS Reference Manual, from IEEE Std 1003.1, 2004 Edition,
Standard for Information Technology -- Portable Operating System
Interface (POSIX), The Open Group Base Specifications Issue 6,
Copyright (C) 2001-2004 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy
between these versions and the original IEEE and The Open Group
Standard, the original IEEE and The Open Group Standard is the referee
document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html.

This notice shall appear on any product containing this material.

The contents of this file are subject to the terms of the
Common Development and Distribution License (the "License").
You may not use this file except in compliance with the License.

You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
or http://www.opensolaris.org/os/licensing.
See the License for the specific language governing permissions
and limitations under the License.

When distributing Covered Code, include this CDDL HEADER in each
file and include the License file at usr/src/OPENSOLARIS.LICENSE.
If applicable, add the following below this CDDL HEADER, with the
fields enclosed by brackets "[]" replaced with your own identifying
information: Portions Copyright [yyyy] [name of copyright owner]


Copyright (c) 1992, X/Open Company Limited. All Rights Reserved.
Portions Copyright (c) 2000, Sun Microsystems, Inc. All Rights Reserved.

INET_ADDR 3XNET "Jun 10, 2002"
NAME
inet_addr, inet_network, inet_makeaddr, inet_lnaof, inet_netof, inet_ntoa - Internet address manipulation
SYNOPSIS

cc [ flag ... ] file ... -lxnet [ library ... ]
#include <arpa/inet.h>

in_addr_t inet_addr(const char *cp);

in_addr_t inet_lnaof(struct in_addr in);

struct in_addr inet_makeaddr(in_addr_t net, in_addr_t lna);

in_addr_t inet_netof(struct in_addr in);

in_addr_t inet_network(const char *cp);

char *inet_ntoa(struct in_addr in);
DESCRIPTION

The inet_addr() function converts the string pointed to by cp, in the Internet standard dot notation, to an integer value suitable for use as an Internet address.

The inet_lnaof() function takes an Internet host address specified by in and extracts the local network address part, in host byte order.

The inet_makeaddr() function takes the Internet network number specified by net and the local network address specified by lna, both in host byte order, and constructs an Internet address from them.

The inet_netof() function takes an Internet host address specified by in and extracts the network number part, in host byte order.

The inet_network() function converts the string pointed to by cp, in the Internet standard dot notation, to an integer value suitable for use as an Internet network number.

The inet_ntoa() function converts the Internet host address specified by in to a string in the Internet standard dot notation.

All Internet addresses are returned in network order (bytes ordered from left to right).

Values specified using dot notation take one of the following forms: a.b.c.d

When four parts are specified, each is interpreted as a byte of data and assigned, from left to right, to the four bytes of an Internet address.

a.b.c

When a three-part address is specified, the last part is interpreted as a 16-bit quantity and placed in the rightmost two bytes of the network address. This makes the three-part address format convenient for specifying Class B network addresses as 128.net.host.

a.b

When a two-part address is supplied, the last part is interpreted as a 24-bit quantity and placed in the rightmost three bytes of the network address. This makes the two-part address format convenient for specifying Class A network addresses as net.host.

a

When only one part is given, the value is stored directly in the network address without any byte rearrangement.

All numbers supplied as parts in dot notation may be decimal, octal, or hexadecimal, that is, a leading 0x or 0X implies hexadecimal, as specified in the ISO C standard; otherwise, a leading 0 implies octal; otherwise, the number is interpreted as decimal.

USAGE

The return value of inet_ntoa() may point to static data that may be overwritten by subsequent calls to inet_ntoa().

RETURN VALUES

Upon successful completion, inet_addr() returns the Internet address. Otherwise, it returns (in_addr_t)(-1).

Upon successful completion, inet_network() returns the converted Internet network number. Otherwise, it returns (in_addr_t)(-1).

The inet_makeaddr() function returns the constructed Internet address.

The inet_lnaof() function returns the local network address part.

The inet_netof() function returns the network number.

The inet_ntoa() function returns a pointer to the network address in Internet-standard dot notation.

ERRORS

No errors are defined.

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface Stability Standard
MT-Level MT-Safe
SEE ALSO

endhostent(3XNET), endnetent(3XNET), attributes(5), standards(5)