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INET_ADDR(P)			    POSIX Programmer's Manual			     INET_ADDR(P)

NAME
       inet_addr, inet_ntoa - IPv4 address manipulation

SYNOPSIS
       #include <arpa/inet.h>

       in_addr_t inet_addr(const char *cp);
       char *inet_ntoa(struct in_addr in);

DESCRIPTION
       The  inet_addr()  function shall convert the string pointed to by cp, in the standard IPv4
       dotted decimal notation, to an integer value suitable for use as an Internet address.

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

       The  inet_ntoa()  function  need  not  be reentrant. A function that is not required to be
       reentrant is not required to be thread-safe.

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

       Values specified using IPv4 dotted decimal notation take one of the following forms:

       a.b.c.d
	      When  four  parts  are  specified,  each shall be 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 shall  be  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 shall be 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 shall be  stored  directly  in  the  network
	      address without any byte rearrangement.

       All  numbers  supplied  as parts in IPv4 dotted decimal notation may be decimal, octal, or
       hexadecimal, as specified in the ISO C standard (that is, a leading 0x or 0X implies hexa-
       decimal;  otherwise,  a leading '0' implies octal; otherwise, the number is interpreted as
       decimal).

RETURN VALUE
       Upon successful completion, inet_addr() shall return the Internet address.  Otherwise,  it
       shall return ( in_addr_t)(-1).

       The  inet_ntoa()  function shall return a pointer to the network address in Internet stan-
       dard dot notation.

ERRORS
       No errors are defined.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       The return value of inet_ntoa() may point to static data that may be overwritten by subse-
       quent calls to inet_ntoa().

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       endhostent()  ,	endnetent()  ,	the  Base  Definitions	volume	of  IEEE Std 1003.1-2001,
       <arpa/inet.h>

COPYRIGHT
       Portions of this text are reprinted and	reproduced  in	electronic  form  from	IEEE  Std
       1003.1,	2003  Edition,	Standard  for Information Technology -- Portable Operating System
       Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003  by
       the  Institute  of  Electrical  and  Electronics Engineers, Inc and The Open Group. In the
       event of any discrepancy between this version and the original IEEE  and  The  Open  Group
       Standard, the original IEEE and The Open Group Standard is the referee document. The orig-
       inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group			       2003				     INET_ADDR(P)
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