netinet/in.h - Internet Protocol family

最新推荐文章于 2024-09-11 21:14:12 发布

yanook

最新推荐文章于 2024-09-11 21:14:12 发布

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文章标签： internet header structure macros types socket

本文介绍了网络编程中重要的头文件<netinet/in.h>，详细解释了其中定义的数据类型、结构体和宏，包括in_port_t、in_addr_t、in_addr、sockaddr_in等，并列举了它们在网络编程中的应用。

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NAME

netinet/in.h - Internet Protocol family

SYNOPSIS



#include <netinet/in.h>

DESCRIPTION

When header file <netinet/in.h> is included, the following types are defined through typedef.

in_port_t
An unsigned integral type of exactly 16 bits.
in_addr_t
An unsigned integral type of exactly 32 bits.

The <netinet/in.h> header defines the in_addr structure that includes at least the following member:
in_addr_t      s_addr
The <netinet/in.h> header defines the sockaddr_in structure that includes at least the following member:
sa_family_t    sin_family
in_port_t      sin_port
struct in_addr sin_addr
unsigned char  sin_zero[8]
The sockaddr_in structure is used to store addresses for the Internet protocol family. Values of this type must be cast to struct sockaddr for use with the socket interfaces defined in this document.
The <netinet/in.h> header defines the type sa_family_t as described in <sys/socket.h>.

The <netinet/in.h> header defines the following macros for use as values of the level argument of getsockopt() and setsockopt():

IPPROTO_IP
Dummy for IP.
IPPROTO_ICMP
Control message protocol.
IPPROTO_TCP
TCP.
IPPROTO_UDP
User datagram protocol.

The <netinet/in.h> header defines the following macros for use as destination addresses for connect(), sendmsg() and sendto():

INADDR_ANY
Local host address.
INADDR_BROADCAST
Broadcast address.

ntohl(), ntohs(), htonl() and htons() as defined in the description of <arpa/inet.h> are available. Inclusion of the <netinet/in.h> header may also make visible all symbols from <arpa/inet.h>.