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INET_NTOP(3) Linux Programmer's Manual INET_NTOP(3)

NAME

     inet_ntop - convert IPv4 and IPv6 addresses from binary to text form

SYNOPSIS

     #include <arpa/inet.h>

     const char *inet_ntop(int af, const void *src,
                           char *dst, socklen_t size);

DESCRIPTION

     This  function  converts  the  network  address structure src in the af
     address family into a character string.  The resulting string is copied
     to the buffer pointed to by dst, which must be a non-null pointer.  The
     caller specifies the number of bytes available in this  buffer  in  the
     argument size.

     inet_ntop()  extends  the  inet_ntoa(3)  function  to  support multiple
     address families, inet_ntoa(3) is now considered to  be  deprecated  in
     favor  of  inet_ntop().   The  following address families are currently
     supported:

     AF_INET
            src points to a struct in_addr (in network byte order) which  is
            converted  to an IPv4 network address in the dotted-decimal for-
            mat,  "ddd.ddd.ddd.ddd".   The  buffer  dst  must  be  at  least
            INET_ADDRSTRLEN bytes long.

     AF_INET6
            src points to a struct in6_addr (in network byte order) which is
            converted to a representation of this address in the most appro-
            priate IPv6 network address format for this address.  The buffer
            dst must be at least INET6_ADDRSTRLEN bytes long.

RETURN VALUE

     On success, inet_ntop() returns a non-null pointer  to  dst.   NULL  is
     returned if there was an error, with errno set to indicate the error.

ERRORS

     EAFNOSUPPORT
            af was not a valid address family.

     ENOSPC The  converted  address  string  would  exceed the size given by
            size.

ATTRIBUTES

     For  an  explanation  of  the  terms  used   in   this   section,   see
     attributes(7).

     +------------+---------------+----------------+
     |Interface   | Attribute     | Value          |
     +------------+---------------+----------------+
     |inet_ntop() | Thread safety | MT-Safe locale |
     +------------+---------------+----------------+

CONFORMING TO

     POSIX.1-2001,  POSIX.1-2008.   Note  that  RFC 2553 defines a prototype
     where the last argument size is of type size_t.   Many  systems  follow
     RFC 2553.   Glibc  2.0  and  2.1  have  size_t,  but 2.2 and later have
     socklen_t.

BUGS

     AF_INET6 converts IPv4-mapped IPv6 addresses into an IPv6 format.

EXAMPLE

     See inet_pton(3).