sockaddr_in(3type) sockaddr_in(3type) sockaddr_in, in_addr, in_addr_t, in_port_t - IPv4 (libc) #include struct sockaddr_in { sa_family_t sin_family; /* AF_INET */ in_port_t sin_port; /* */ struct in_addr sin_addr; /* IPv4 */ }; struct in_addr { in_addr_t s_addr; }; typedef uint32_t in_addr_t; typedef uint16_t in_port_t; sockaddr_in IPv4. .sin_port .sin_addr . POSIX.1-2024. POSIX.1-2001. sockaddr(3type), sockaddr_in6(3type) 3 . . : . 6.18 25 2025 sockaddr_in(3type)