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inet_pton(3)
NAME
  inet_pton - Convert a text string to a numeric address

SYNOPSIS
  #include <arpa/inet.h>

  int inet_pton(
	  int af,
	  const char *src,
	  void *dst );

LIBRARY
  Standard C Library (libc)

PARAMETERS
  af  Specifies the address family.  Valid values are AF_INET for an Internet
      Protocol Version 4 (IPv4) address and AF_INET6 for an IPv6 address.

  src Points to the address text string to be converted.

  dst Points to a buffer that is to contain the numeric address.

DESCRIPTION
  The use of this routine is deprecated.  Use the getaddrinfo(3) routine
  instead; it is also protocol-independent.

  The inet_pton() function converts a text string to a numeric value in
  Internet network-byte order.

  If the af parameter is AF_INET, the function accepts a string in the
  standard IPv4 dotted-decimal form:

       ddd.ddd.ddd.ddd

  In this format, ddd is a one to three digit decimal number between 0 and
  255.

  If the af parameter is AF_INET6, the function accepts a string in the
  following form:

       x:x:x:x:x:x:x:x

  In this format, x is hexadecimal value of a 16-bit piece of the address.

  IPv6 addresses can contain long strings of zero (0) bits. To make it easier
  to write these addresses, you can use double colon characters (::) one time
  in an address to represent 1 or more 16-bit groups of zeros.

  For mixed IPv4 and IPv6 environments, the following form is also accepted:

       x:x:x:x:x:x:ddd.ddd.ddd.ddd

  In this form, x is hexadecimal value of a 16-bit piece of the address and
  ddd is a one to three digit decimal value between 0 and 255 that represents
  the IPv4 address.  See RFC 2373 for more information on IPv6 addressing
  formats.

  The calling application is responsible for ensuring that the buffer
  referred to by the dst parameter is large enough to hold the numeric
  address. AF_INET addresses require 4 bytes and AF_INET6 addresses require
  16 bytes.

RETURN VALUES
  Upon successful completion, the inet_pton() function returns 1.  If the
  input string is not a valid IPv4 dotted-decimal string or a valid IPv6
  address string, the function returns 0.  If any other error occurs, the
  function returns -1.

ERRORS
  If the inet_pton() routine call fails, errno is set to one of the following
  values:

  [EAFNOSUPPORT]
      The address family specified in the af parameter is unknown.

SEE ALSO
  Functions: getaddrinfo(3), inet_ntop(3).

  RFC 2373, IP Version 6 Addressing Architecture

  Network Programmer's Guide

Index for Section 3

Alphabetical listing for I

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