socket状态表网络编程头文件网络地址转换 - 网络

一、socket状态表

状态	描述	备注
ESTABLISHED	The socket has an established connection.
SYN_SENT	The socket is actively attempting to establish a connection.
SYN_RECV	A connection request has been received from the network.
FIN_WAIT1	The socket is closed, and the connection is shutting down.
FIN_WAIT2	Connection is closed, and the socket is waiting for a shutdown from the remote end.
TIME_WAIT	The socket is waiting after close to handle packets still in the network.
CLOSED	The socket is not being used.
CLOSE_WAIT	The remote end has shut down, waiting for the socket to close.
LAST_ACK	The remote end has shut down, and the socket is closed. Waiting for acknowledgement.
LISTEN	The socket is listening for incoming connections.
CLOSING	Both sockets are shut down but we still don’t have all our data sent.
UNKNOWN	The state of the socket is unknown.

二、网络编程头文件

ls /usr/include/sys | grep socket

socket.h
socketvar.h

ls /usr/include/arpa | cat
ftp.h
inet.h
nameser_compat.h
nameser.h
telnet.h
tftp.h

ls /usr/include/netinet | cat
ether.h
icmp6.h
if_ether.h
if_fddi.h
if_tr.h
igmp.h
in.h
in_systm.h
ip6.h
ip.h
ip_icmp.h
tcp.h
udp.h

三、网络地址转换

1、inet_pton输出大端模式；

2、下载代码：ip_convert.cpp

3、编译代码：g++ -g ip_convert.cpp -o ip_convert

class IPConvert
{
public:
static void getStringIP(uint32_t ip, char *strIP)
{
in_addr addr;
addr.s_addr = ip;
inet_ntop(AF_INET, (void *)&addr, strIP, INET_ADDRSTRLEN);
}
static void getStringIP(in_addr &addr, char *strIP)
{
inet_ntop(AF_INET, (void *)&addr, strIP, INET_ADDRSTRLEN);
}
static in_addr getIntIP(const char *strIP)
{
in_addr addr;
inet_pton(AF_INET, strIP, (void *)&addr);
return addr;
}
};

void testIPConvert()
{
in_addr address;
char strIP[INET_ADDRSTRLEN];
memset(strIP, 0, INET_ADDRSTRLEN);
IPConvert::getStringIP(338799626, strIP);
printf("%s\n", strIP);
address = IPConvert::getIntIP("255.255.255.255");
printf("%d\n", address.s_addr);
IPConvert::getStringIP(address, strIP);
printf("%s\n", strIP);
}