Manpages - inet_ntop.3

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

  #include <arpa/inet.h>

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

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.

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.

EAFNOSUPPORT

af was not a valid address family.

ENOSPC

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

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

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.

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

See *inet_pton*(3).

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

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