IOS socket Programming (Getting started)

1. C-based BSD socket (a common network interface in UNIX systems )

Feel BSD sockets easiest to understand, easiest to get started with, most flexible but most difficult to use, especially for large projects

Need to import header file

#import <sys/socket.h> #import <netdb.h>

Server-side

    int LISTENFD, CONNFD;    struct sockaddr_in servaddr;    Char buff[4096];    Long N;        int i=100; Create socket if ((LISTENFD = socket (af_inet, sock_stream, 0)) = =-1) {printf ("Create Socket Error:%s (errno:%d)        \ n ", Strerror (errno), errno);    Return    }//Initialize IP address memset (&servaddr, 0, sizeof (SERVADDR));    servaddr.sin_family = af_inet;    SERVADDR.SIN_ADDR.S_ADDR = htonl (Inaddr_any); Servaddr.sin_port = htons (8088);//Bind the URL port if (Bind (LISTENFD, (struct sockaddr*) &servaddr, s) as the port URL requested by the client//        Izeof (servaddr)) = =-1) {printf ("Bind socket Error:%s (errno:%d) \ n", Strerror (errno), errno);    Return }//Listening URL port if (listen (LISTENFD) = =-1) {printf ("Listen socket Error:%s (errno:%d) \ n", Strerror (errno        ), errno);    Return    }//Accept data from the server printf ("======waiting for client ' s request======\n"); while (i>0) {if (CONNFD = Accept (LISTENFD, (struct sockaddr*) null, NULL))= =-1) {printf ("Accept socket Error:%s (errno:%d)", Strerror (errno), errno);        Continue        } n = recv (CONNFD, Buff, MAXLINE, 0);        Buff[n] = ' + ';        printf ("Recv msg from client:%s\n", buff);    Close (CONNFD); }//Close socket Close (LISTENFD);

Client

-(void) Senddatatoserverurl: (Nsurl *) url{int sockfd;    Char sendline[4096];    struct sockaddr_in servaddr;        NSString * host = [URL host]; Create socket if ((SOCKFD = socket (af_inet, sock_stream, 0)) < 0) {printf ("Create Socket Error:%s (errno:%d) \ n        ", Strerror (errno), errno);    Return }//Initialize IP address struct hostent * hostent = gethostbyname ([host utf8string]);//obtain IP information by domain name if (NULL = = Hostent        {NSLog (@ "Resolve Domain name failed");    Return        } struct in_addr * remoteinaddr = (struct in_addr *) hostent->h_addr_list[0];    memset (&servaddr, 0, sizeof (SERVADDR));    servaddr.sin_family = af_inet;    Servaddr.sin_port = htons (8088);        SERVADDR.SIN_ADDR = *remoteinaddr; Link TCP Server (based on IP address) if (Connect (sockfd, struct sockaddr*) &servaddr, sizeof (SERVADDR)) < 0) {printf ("Connec        T error:%s (errno:%d) \ n ", Strerror (errno), errno);    Return    }//Send string to the TCP server printf ("Send msg to server: \ n");Fgets (Sendline, 4096, stdin); if (Send (SOCKFD, Sendline, strlen (Sendline), 0) < 0) {printf ("Send msg Error:%s (errno:%d) \ n", Strerror (Errn        o), errno);    Return }//Closes socket close (SOCKFD);}

2.FCSocket interface more than BSD socket

Server-side and BSD sockets are a bit similar,

The client is completely different from the BSD socket, using an input/output stream.

Server-side

Receive message listener static void Handleconnect (Cfsocketref sock, Cfsocketcallbacktype type, cfdataref address, const void *data, void * Info) {NSLog (@ "received message");}    -(void) openfcsocket{//Create socket const Cfsocketcontext Socketctxt = {0, (__bridge void *) self, NULL, NULL, NULL};                                           Cfsocketref Cfsocket = cfsocketcreate (Kcfallocatordefault,                                           Pf_inet, Sock_stream,                                           Ipproto_tcp, Kcfsocketacceptcallback,        (cfsocketcallback) handleconnect,//receive information callback &socketctxt);        if (Cfsocket = = NULL) {NSLog (@ "Create socket failed");    Return    }//Initialize IP address struct sockaddr_in sin;    memset (&sin, 0, sizeof (sin));    Sin.sin_len = sizeof (SIN); sin.sin_family = af_inet; /* Address family */sin.siN_port = htons (8088);            /* Or a specific port */sin.sin_addr.s_addr= Inaddr_any;                                    Bind URL Port cfdataref sincfd = Cfdatacreate (Kcfallocatordefault,        (UInt8 *) &sin, sizeof (sin));    if (kcfsocketsuccess! = cfsocketsetaddress (Cfsocket, SINCFD)) {NSLog (@ "Bind URL port failed");            } cfrelease (SINCFD);                                                                  Add socket to run loop cfrunloopsourceref Socketsource = Cfsocketcreaterunloopsource ( Kcfallocatordefault, CFSOC    Ket, 0);                       Cfrunloopaddsource (Cfrunloopgetcurrent (), Socketsource, Kcfrunloopdefaultmode);}

Client

NSString *host = @ "127.0.0.1";    int port = 8088;    Create an input/output stream cfreadstreamref Readstream;    Cfwritestreamref Writestream;                                       Cfstreamcreatepairwithsockettohost (Kcfallocatordefault, (__bridge cfstringref) host,    Port, &readstream, &writestream);    Nsinputstream *inputstream = (__bridge nsinputstream *) Readstream;        Nsoutputstream *outputstream = (__bridge nsoutputstream *) Writestream; if (InputStream = = Nil | | outputstream = nil) {NSLog (@ "Stream creation failed!)        ");    return;    }//start the input/output stream [InputStream open];            [OutputStream Open];    Send data NSData *outgoingdatabuffer = [@ "testdata" datausingencoding:nsutf8stringencoding];    Nsinteger writtenbytes = [OutputStream write:outgoingDataBuffer.bytes maxLength:outgoingDataBuffer.length];        if (writtenbytes = =-1) {NSLog (@ "send failed");    Return } NSLog (@ "send success");

3. The Cocoaasyncsocket encapsulates the Cfsocket

Implements the TCP,UDP, joins the asynchronous thread, disconnects the heavy connection, Tls/ssl and so on, actually needs to implement in the development the thing.

If there's no time to reinvent the wheel, it's good to use such a third-party framework.

IOS socket Programming (Getting started)