socket programming in c

" "The Soket client mainly completes the following steps: 1. Establish a soket socket (to interpret a socket as a channel) 2. Establish a connection 3. Send an HTTP request to the server 4. Data received 5. Close connection 6. Data processed locally" "ImportSocket#Importing the socket library" "establish a socket,af_inet to represent the IPv4 protocol (AF_INET6 represents the IPv6 protocol) and sock_stream

Sockets are also commonly referred to as "sockets," which describe IP addresses and ports, and are a handle to a chain of communication, where applications usually make requests to the network through "sockets" or respond to network requests.Sockets originate from UNIX, and one of the basic philosophies of unix/linux is "Everything is file", and the file is operated with "open" "Read and Write" "Off" mode. Socket is an implementation of this pattern, the socket is a special kind of file, some of

Method One:Socket Socket=nulltry{ServerSocket serversocket=nwe serversocket (8080)while (true) {Socket=serversocket.apccet ();New Serverthread (socket). Start ();}}catch (IOException e) {E.printstacktrace ()}Method Two:public class Serverthread extends thread{private socket socket;Public ServerSocket (socket) {This.socket=socket;}public void Run () {Replication Run methodInputStream Is=null;OutputStream Os=null;String ip=socket.getlocaladdress (). gethostaddress ();String Port=socket.getport ();

:#Infinite Loops - Print('try to connect the client ... ') -Tcpclisock, addr = Tcpsersock.accept ()#waiting to accept the connection + Print('the link is successful and the client address is:', addr) - + whileTrue: Adata = TCPCLISOCK.RECV (Bufsiz)#receive data, Bufsiz is the buffer size at if notData Break #if data is empty, jump out of the loop - Print(Data.decode ()) - -msg ='{} The server has received [auto Reply]'. Format (CTime ()) - Tcpclisock.send (Msg.

The responsibility of the middleware program:1) to the cabinet machine to provide soket long connection server side, is Soket server. can provide tens of thousands of simultaneous client connections. In order to respond to control requests in real time, the middleware must always know the online status of a particular cabinet, and external requests can determine if the message can be forwarded.The middlewar

1 #udp_gb_server.py2 " "Server side (UDP protocol LAN broadcast)" "3 4 ImportSocket5 6s =Socket.socket (socket.af_inet, socket. SOCK_DGRAM)7S.setsockopt (socket. Sol_socket, SOCKET. So_broadcast, 1)8 9PORT = 1060Ten OneNetwork ='' AS.sendto ('Client Broadcast message!'. Encode ('Utf-8'), (Network, PORT))#udp_gb_client.py" "client (UDP protocol LAN broadcast)" "ImportSockets=Socket.socket (socket.af_inet, socket. SOCK_DGRAM) s.setsockopt (socket. Sol_socket, SOCKET. So_broadcast,1) PORT= 1060S.b

" "Client" " fromSocketImport*Host='localhost' #Local server addressPort = 12345#client port (ensure that the port is consistent with the serverBufsiz = 2048#Cache SizeADDC = (host, port)#address + PortUdpclisock= Socket (af_inet, SOCK_DGRAM)#Create a socket type for UDP. whiletrue:msg= Input ('The client says:')#input DataUdpclisock.sendto (Msg.encode ('Utf-8'), ADDC) data, adds=Udpclisock.recvfrom (Bufsiz)if notData Break Print('Server Answer:', Data.decode ('Utf-8') ) Udpclisock.close (

non-blocking, server implementation mode for a valid request for a thread, the client I/O requests are completed by the OS before notifying the server application to start the thread for processing,BIO, NIO, AIO application Scenario analysis:The bio method is suitable for a small and fixed number of connections, which requires a high level of server resources, and is limited to applications, JDK1.4 the only choice before, but the program is intuitive and easy to understand.The NIO approach is s

ArticleDirectory Preface Development Process Summary Follow-up Preface In this project, pixysoft. Framework. noebe. Sockets exposes database operations using socket to implement LAN calls. Firewall traversal, lan-public

Document directory Preface Development Process Summary Follow-up Preface In this project, Pixysoft. Framework. Noebe. Sockets exposes database operations using socket to implement LAN calls. Firewall traversal, lan-public network connection,

1, blocking mode and non-blocking mode in the return value of the recv what the meaning of each representative. There is no difference. (As far as I am aware of the blocking and non-blocking recv return values are not differentiated, are 0 received

u_char makes the multicast loop valid or invalidThe ip_mreq structure is defined in the header file:[Code: 1: 63724de67f]Struct ip_mreq {Struct in_addr imr_multiaddr;/* IP multicast address of Group */Struct in_addr imr_interface;/* local IP address of interface */};[/Code: 1: 63724de67f]To add a process to a multicast group, use the setsockopt () function of soket to send this option. The option type is ip_mreq structure. Its first field imr_multiad

groupIp_multicast_if struct ip_mreq specifies the interface for submitting multicast packetsIp_multicast_ttl u_char specifies the TTL of the subscriber.Ip_multicast_loop u_char makes the multicast loop valid or invalidThe ip_mreq structure is defined in the header file:[Code: 1: 63724de67f]Struct ip_mreq {Struct in_addr imr_multiaddr;/* IP multicast address of Group */Struct in_addr imr_interface;/* local IP address of interface */};[/Code: 1: 63724de67f]If the process needs to be added? To a m

groupIp_multicast_if struct ip_mreq specifies the interface for submitting multicast packetsIp_multicast_ttl u_char specifies the TTL of the subscriber.Ip_multicast_loop u_char makes the multicast loop valid or invalidThe ip_mreq structure is defined in the header file:[Code: 1: 63724de67f]Struct ip_mreq {Struct in_addr imr_multiaddr;/* IP multicast address of Group */Struct in_addr imr_interface;/* local IP address of interface */};[/Code: 1: 63724de67f]If the process needs to be added? To a m

:1:63724de67f]struct Ip_mreq {struct IN_ADDR imr_multiaddr; /* IP multicast address of Group */struct IN_ADDR imr_interface; /* Local IP Address of interface */};[/code:1:63724de67f]If the process is to be added to a multicast group, this option is sent with the Soket setsockopt () function. The option type is the IP_MREQ structure, its first field imr_multiaddr specifies the address of the multicast group, and the second field imr_interface specifies

: Variable length, message content;This approach has the same advantages: all data transmission has a uniform standard. The disadvantage is that some commands have a fixed known length, wasting some bandwidth. In the future we will change to a mixed method.　　The next thing to decide is the server model: "Non-blocking soket, no threads", or "blocking soket, using threads". There are pros and cons to both met

1. closesocket (typically does not close immediately and undergoes a time_wait process) wants to continue reusing the socket:BOOL breuseaddr=true;setsockopt (S,sol_socket, SO_REUSEADDR, (const char*) breuseaddr,sizeof (BOOL)); 2. If the soket that is already in the connection state is forced to close after calling Closesocket, do not experienceThe process of time_wait:BOOL Bdontlinger = FALSE;setsockopt (S,sol_socket,so_dontlinger, (const char*) bdont

make group broadcast text loop valid or invalidThe IP_MREQ structure is defined in the header file:[code:1:63724de67f]struct Ip_mreq {struct IN_ADDR imr_multiaddr; /* IP multicast address of Group */struct IN_ADDR imr_interface; /* Local IP Address of interface */};[/code:1:63724de67f]If the process is to be added to a multicast group. Use the Soket setsockopt () function to send this option. The option type is the IP_MREQ structure, its first field

the TTL of the subscriber.Ip_multicast_loop u_char makes the multicast loop valid or invalidThe ip_mreq structure is defined in the header file:[Code: 1: 63724de67f]Struct ip_mreq {Struct in_addr imr_multiaddr;/* IP multicast address of Group */Struct in_addr imr_interface;/* local IP address of interface */};[/Code: 1: 63724de67f]To add a process to a multicast group, use the setsockopt () function of soket to send this option. The option type is ip

multicast groupIP_MULTICAST_IF struct ip_mreq specifies the interface for submitting multicast packetsIP_MULTICAST_TTL u_char specifies the TTL of the subscriber.IP_MULTICAST_LOOP u_char makes the multicast loop valid or invalidThe ip_mreq structure is defined in the header file:[Code: 1: 63724de67f]Struct ip_mreq {Struct in_addr imr_multiaddr;/* IP multicast address of group */Struct in_addr imr_interface;/* local IP address of interface */};[/Code: 1: 63724de67f]To add a process to a multicas