inet_ntop(3)

1INET_NTOP(3)               Linux Programmer's Manual              INET_NTOP(3)
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NAME

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

9       #include <arpa/inet.h>
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11       const char *inet_ntop(int af, const void *restrict src,
12                             char *restrict dst, socklen_t size);
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DESCRIPTION

15       This  function converts the network address structure src in the af ad‐
16       dress family into a character string.  The resulting string  is  copied
17       to the buffer pointed to by dst, which must be a non-null pointer.  The
18       caller specifies the number of bytes available in this  buffer  in  the
19       argument size.
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21       inet_ntop()  extends  the inet_ntoa(3) function to support multiple ad‐
22       dress families, inet_ntoa(3) is now considered to be deprecated in  fa‐
23       vor  of inet_ntop().  The following address families are currently sup‐
24       ported:
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26       AF_INET
27              src points to a struct in_addr (in network byte order) which  is
28              converted  to an IPv4 network address in the dotted-decimal for‐
29              mat,  "ddd.ddd.ddd.ddd".   The  buffer  dst  must  be  at  least
30              INET_ADDRSTRLEN bytes long.
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32       AF_INET6
33              src points to a struct in6_addr (in network byte order) which is
34              converted to a representation of this address in the most appro‐
35              priate IPv6 network address format for this address.  The buffer
36              dst must be at least INET6_ADDRSTRLEN bytes long.
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RETURN VALUE

39       On success, inet_ntop() returns a non-null pointer to dst.  NULL is re‐
40       turned if there was an error, with errno set to indicate the error.
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ERRORS

43       EAFNOSUPPORT
44              af was not a valid address family.
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46       ENOSPC The  converted  address  string  would  exceed the size given by
47              size.
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ATTRIBUTES

50       For an  explanation  of  the  terms  used  in  this  section,  see  at‐
51       tributes(7).
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53       ┌─────────────────────────────────────┬───────────────┬────────────────┐
54       │Interface                            │ Attribute     │ Value          │
55       ├─────────────────────────────────────┼───────────────┼────────────────┤
56       │inet_ntop()                          │ Thread safety │ MT-Safe locale │
57       └─────────────────────────────────────┴───────────────┴────────────────┘
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CONFORMING TO

60       POSIX.1-2001,  POSIX.1-2008.   Note  that  RFC 2553 defines a prototype
61       where the last argument size is of type size_t.   Many  systems  follow
62       RFC 2553.   Glibc  2.0  and  2.1  have  size_t,  but 2.2 and later have
63       socklen_t.
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BUGS

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

69       See inet_pton(3).
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COLOPHON

75       This page is part of release 5.12 of the Linux  man-pages  project.   A
76       description  of  the project, information about reporting bugs, and the
77       latest    version    of    this    page,    can     be     found     at
78       https://www.kernel.org/doc/man-pages/.
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82Linux                             2021-03-22                      INET_NTOP(3)