1sockaddr(3type) sockaddr(3type)
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6 sockaddr, sockaddr_storage, sockaddr_in, sockaddr_in6, sockaddr_un,
7 socklen_t, in_addr, in6_addr, in_addr_t, in_port_t, - socket address
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10 Standard C library (libc)
11
13 #include <sys/socket.h>
14
15 struct sockaddr {
16 sa_family_t sa_family; /* Address family */
17 char sa_data[]; /* Socket address */
18 };
19
20 struct sockaddr_storage {
21 sa_family_t ss_family; /* Address family */
22 };
23
24 typedef /* ... */ socklen_t;
25 typedef /* ... */ sa_family_t;
26
27 Internet domain sockets
28 #include <netinet/in.h>
29
30 struct sockaddr_in {
31 sa_family_t sin_family; /* AF_INET */
32 in_port_t sin_port; /* Port number */
33 struct in_addr sin_addr; /* IPv4 address */
34 };
35
36 struct sockaddr_in6 {
37 sa_family_t sin6_family; /* AF_INET6 */
38 in_port_t sin6_port; /* Port number */
39 uint32_t sin6_flowinfo; /* IPv6 flow info */
40 struct in6_addr sin6_addr; /* IPv6 address */
41 uint32_t sin6_scope_id; /* Set of interfaces for a scope */
42 };
43
44 struct in_addr {
45 in_addr_t s_addr;
46 };
47
48 struct in6_addr {
49 uint8_t s6_addr[16];
50 };
51
52 typedef uint32_t in_addr_t;
53 typedef uint16_t in_port_t;
54
55 UNIX domain sockets
56 #include <sys/un.h>
57
58 struct sockaddr_un {
59 sa_family_t sun_family; /* Address family */
60 char sun_path[]; /* Socket pathname */
61 };
62
64 sockaddr
65 Describes a socket address.
66
67 sockaddr_storage
68 A structure at least as large as any other sockaddr_* address
69 structures. It's aligned so that a pointer to it can be cast as
70 a pointer to other sockaddr_* structures and used to access its
71 fields.
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73 socklen_t
74 Describes the length of a socket address. This is an integer
75 type of at least 32 bits.
76
77 sa_family_t
78 Describes a socket's protocol family. This is an unsigned inte‐
79 ger type.
80
81 Internet domain sockets
82 sockaddr_in
83 Describes an IPv4 Internet domain socket address. The sin_port
84 and sin_addr members are stored in network byte order.
85
86 sockaddr_in6
87 Describes an IPv6 Internet domain socket address. The
88 sin6_addr.s6_addr array is used to contain a 128-bit IPv6 ad‐
89 dress, stored in network byte order.
90
91 UNIX domain sockets
92 sockaddr_un
93 Describes a UNIX domain socket address.
94
96 POSIX.1-2008.
97
99 POSIX.1-2001.
100
101 socklen_t was invented by POSIX. See also accept(2).
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104 socklen_t is also defined in <netdb.h>.
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106 sa_family_t is also defined in <netinet/in.h> and <sys/un.h>.
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109 accept(2), bind(2), connect(2), getpeername(2), getsockname(2), get‐
110 sockopt(2), sendto(2), setsockopt(2), socket(2), socketpair(2), getad‐
111 drinfo(3), gethostbyaddr(3), getnameinfo(3), htonl(3), ipv6(7),
112 socket(7)
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116Linux man-pages 6.04 2023-04-03 sockaddr(3type)