inet_ntop - convert IPv4 and IPv6 addresses from binary to text form
const char *inet_ntop(int af, const void *src,
char *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
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:
- 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.
- 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.
- af was not a valid address family.
- The converted address string would exceed the size given by
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
AF_INET6 converts IPv4-mapped IPv6 addresses into an IPv6 format.
This page is part of release 4.16 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the latest
version of this page, can be found at https://www.kernel.org/doc/man-pages/.