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 ad-
dress 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 ad-
dress families, inet_ntoa(3) is now considered to be deprecated in fa-
vor of inet_ntop(). The following address families are currently sup-
ported:
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 re-
turned 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 at-
tributes(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.
EXAMPLES
See inet_pton(3).
SEE ALSO
getnameinfo(3), inet(3), inet_pton(3)
COLOPHON
This page is part of release 5.07 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/.
Linux 2020-06-09 INET_NTOP(3)