inet_ntop(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | ATTRIBUTES | STANDARDS | HISTORY | BUGS | EXAMPLES | SEE ALSO

inet_ntop(3)            Library Functions Manual            inet_ntop(3)

NAME         top

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

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <arpa/inet.h>

       const char *inet_ntop(int af, const void *restrict src,
                             char dst[restrict .size], socklen_t size);

DESCRIPTION         top

       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 format, "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 appropriate IPv6 network address format for this
              address.  The buffer dst must be at least INET6_ADDRSTRLEN
              bytes long.

RETURN VALUE         top

       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         top

       EAFNOSUPPORT
              af was not a valid address family.

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

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────────┬───────────────┬────────────────┐
       │ Interface                    Attribute     Value          │
       ├──────────────────────────────┼───────────────┼────────────────┤
       │ inet_ntop()                  │ Thread safety │ MT-Safe locale │
       └──────────────────────────────┴───────────────┴────────────────┘

STANDARDS         top

       POSIX.1-2008.

HISTORY         top

       POSIX.1-2001.

       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         top

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

EXAMPLES         top

       See inet_pton(3).

SEE ALSO         top

       getnameinfo(3), inet(3), inet_pton(3)

Linux man-pages (unreleased)     (date)                     inet_ntop(3)

Pages that refer to this page: gethostbyname(3)getipnodebyname(3)getnameinfo(3)inet(3)inet_pton(3)