| INET_NET(3) | Library Functions Manual | INET_NET(3) | 
inet_net_ntop, inet_net_pton
  —
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
char *
  
  inet_net_ntop(int
    af, const void
    *src, int bits,
    char *dst,
    size_t size);
int
  
  inet_net_pton(int
    af, const char
    *src, void *dst,
    size_t size);
inet_net_ntop() function converts an Internet
  network number from network format (usually a struct
  in_addr or some other binary form, in network byte order) to CIDR
  presentation format (suitable for external display purposes). The
  bits argument is the number of bits in
  src that are the network number. It returns
  NULL if an error occurs (in which case
  errno will have been set), or it returns a pointer to
  the destination string.
The inet_net_pton() function converts a
    presentation format Internet network number (that is, printable form as held
    in a character string) to network format (usually a struct
    in_addr or some other internal binary representation, in network byte
    order). It returns the number of bits (either computed based on the class,
    or specified with /CIDR), or -1 if a failure occurred (in which case
    errno will have been set).
The currently supported values for af are
    AF_INET and AF_INET6. The
    size argument is the size of the result buffer
    dst.
a.b.c.d/bits a.b.c.d a.b.c a.b a
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
    network number. Note that when an Internet network number is viewed as a
    32-bit integer quantity on a system that uses little-endian byte order (such
    as the Intel 386, 486, and Pentium processors) the bytes referred to above
    appear as “d.c.b.a”. That is,
    little-endian bytes are ordered from right to left.
When a three part number is specified, the last part is
    interpreted as a 16-bit quantity and placed in the rightmost two bytes of
    the Internet network number. This makes the three part number format
    convenient for specifying Class B network numbers as
    “128.net.host”.
When a two part number is supplied, the last part is interpreted
    as a 24-bit quantity and placed in the rightmost three bytes of the Internet
    network number. This makes the two part number format convenient for
    specifying Class A network numbers as
    “net.host”.
When only one part is given, the value is stored directly in the Internet network number without any byte rearrangement.
All numbers supplied as “parts” in a
    ‘.’ notation may be decimal, octal, or
    hexadecimal, as specified in the C language (i.e., a leading 0x or 0X
    implies hexadecimal; otherwise, a leading 0 implies octal; otherwise, the
    number is interpreted as decimal).
inet_net_ntop() and
  inet_net_pton() functions may fail with
EAFNOSUPPORT]AF_INET or AF_INET6.EMSGSIZE]The inet_net_ntop() function may fail
  with
EINVAL]The inet_net_pton() function may fail
  with
ENOENT]inet_net_ntop() and
  inet_net_pton() functions appeared in BIND 4.9.4 and
  thence NetBSD 1.3. Support for
  AF_INET6 appeared in NetBSD
  1.6.
| July 20, 2012 | NetBSD 9.3 |