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inet_addr(3)
NAME
  inet_addr - Translate an Internet network address string to an Internet
  address integer

SYNOPSIS
  #include <arpa/inet.h>

  in_addr_t inet_addr(
	  const char *string );

LIBRARY
  Standard C Library (libc)

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  inet_addr():	XNS4.0, XNS5.0

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

PARAMETERS
  string
      Defines an Internet dot-formatted address character string of the form
      a.b.c.d, where a, b, c, and d may be expressed as decimal, octal, or
      hexadecimal integers in the C idiom.

DESCRIPTION
  The inet_addr() function translates a dot-formatted Internet character
  address string to an Internet address integer. The Internet address integer
  is returned as a network byte-ordered integer.

  Values specified using dot notation take on one of the following forms:

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

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

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

  All numbers supplied as parts in dot notation can be decimal, octal, or
  hexadecimal, as specified in the ISO C standard. A leading 0x or 0X implies
  hexadecimal and a leading 0 implies octal.  Otherwise, the number is
  interpreted as decimal.

NOTES
  The dot-formatted network-address a.b.c.d is returned as the machine
  integer dcba.

RETURN VALUES
  Upon successful completion, the inet_addr() function returns an equivalent
  network byte-ordered address integer.	 Otherwise, it returns (in_addr_t)-1.

ERRORS
  Current industry standards for inet_addr() do not define error values.

SEE ALSO
  Functions: inet_netof(3), inet_lnaof(3), inet_makeaddr(3), inet_network(3),
  inet_ntoa(3)

  Standards: standards(5)

  Network Programmer's Guide

Index for Section 3

Alphabetical listing for I

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