iOS socket TCP UDP

TCP:

服务器：

#import <Foundation/Foundation.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
int main(int argc, const char * argv[])
{
    @autoreleasepool {
//
        int err;
        int fd=socket(AF_INET, SOCK_STREAM  , );
        BOOL success=(fd!=-);
//        1
//   2
        if (success) {
            NSLog(@"socket success");
            struct sockaddr_in addr;
            memset(&addr, , sizeof(addr));
            addr.sin_len=sizeof(addr);
            addr.sin_family=AF_INET;
//            =======================================================================
            addr.sin_port=htons();
//        ============================================================================
             addr.sin_addr.s_addr=INADDR_ANY;
            err=bind(fd, (const struct sockaddr *)&addr, sizeof(addr));
            success=(err==);
        }
 //   2
//        ============================================================================
        if (success) {
            NSLog(@"bind(绑定) success");
            err=listen(fd, );//开始监听
            success=(err==);
        }
//    ============================================================================
        //
        if (success) {
            NSLog(@"listen success");
            while (true) {
                struct sockaddr_in peeraddr;
                int peerfd;
                socklen_t addrLen;
                addrLen=sizeof(peeraddr);
                NSLog(@"prepare accept");
                peerfd=accept(fd, (struct sockaddr *)&peeraddr, &addrLen);
                success=(peerfd!=-);
//    ============================================================================
                if (success) {
                    NSLog(@"accept success,remote address:%s,port:%d",inet_ntoa(peeraddr.sin_addr),ntohs(peeraddr.sin_port));
                    char buf[];
                    ssize_t count;
                    size_t len=sizeof(buf);
                    do {
                        count=recv(peerfd, buf, len, );
                        NSString* str = [NSString stringWithCString:buf encoding:NSUTF8StringEncoding];
                        NSLog(@"%@",str);
                    } while (strcmp(buf, "exit")!=);
                }
//    ============================================================================
                close(peerfd);
            }
        }
//3
    }
    return ;
}

客户端：

//
//  main.m
//  kewai_SocketClient
//
#import <Foundation/Foundation.h>
#include <sys/socket.h>
#include <netinet/in.h>
#import <arpa/inet.h>
int main(int argc, const char * argv[])
{
    @autoreleasepool {
     //        1
         int err;
        int fd=socket(AF_INET, SOCK_STREAM, );
        BOOL success=(fd!=-);
        struct sockaddr_in addr;
     //        1
        //
        if (success) {
            NSLog(@"socket success");
            memset(&addr, , sizeof(addr));
            addr.sin_len=sizeof(addr);
            addr.sin_family=AF_INET;
            addr.sin_addr.s_addr=INADDR_ANY;
            err=bind(fd, (const struct sockaddr *)&addr, sizeof(addr));
            success=(err==);
        }
        //   2
        //
        if (success) {
//============================================================================
            struct sockaddr_in peeraddr;
            memset(&peeraddr, , sizeof(peeraddr));
            peeraddr.sin_len=sizeof(peeraddr);
            peeraddr.sin_family=AF_INET;
            peeraddr.sin_port=htons();
//            peeraddr.sin_addr.s_addr=INADDR_ANY;
            peeraddr.sin_addr.s_addr=inet_addr("172.16.10.120");
//            这个地址是服务器的地址，
            socklen_t addrLen;
            addrLen =sizeof(peeraddr);
            NSLog(@"connecting");
            err=connect(fd, (struct sockaddr *)&peeraddr, addrLen);
            success=(err==);
            if (success) {
//                struct sockaddr_in addr;
                err =getsockname(fd, (struct sockaddr *)&addr, &addrLen);
                success=(err==);
//============================================================================
//============================================================================
                if (success) {
                      NSLog(@"connect success,local address:%s,port:%d",inet_ntoa(addr.sin_addr),ntohs(addr.sin_port));
                    char buf[];
                    do {
                        printf("input message:");
                        scanf("%s",buf);
                        send(fd, buf, , );
                    } while (strcmp(buf, "exit")!=);
                }
            }
            else{
                NSLog(@"connect failed");
            }
        }
    //    ============================================================================
        //
    }
    return ;
}

UDP：

服务器：

/*
 *UDP/IP应用编程接口（API）
 *服务器的工作流程：首先调用socket函数创建一个Socket，然后调用bind函数将其与本机
 *地址以及一个本地端口号绑定，接收到一个客户端时，服务器显示该客户端的IP地址，并将字串
 *返回给客户端。
 */
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<errno.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#import <arpa/inet.h>
int main(int argc,char **argv)
{
    int ser_sockfd;
    int len;
    //int addrlen;
    socklen_t addrlen;
    char seraddr[];
    struct sockaddr_in ser_addr;
    /*建立socket*/
    ser_sockfd=socket(AF_INET,SOCK_DGRAM,);
    if(ser_sockfd<)
    {
        printf("I cannot socket success\n");
        return ;
    }
    /*填写sockaddr_in 结构*/
    addrlen=sizeof(struct sockaddr_in);
    bzero(&ser_addr,addrlen);
    ser_addr.sin_family=AF_INET;
    ser_addr.sin_addr.s_addr=htonl(INADDR_ANY);
    ser_addr.sin_port=htons();
    /*绑定客户端*/
    if(bind(ser_sockfd,(struct sockaddr *)&ser_addr,addrlen)<)
    {
        printf("connect");
        return ;
    }
    while()
    {
        bzero(seraddr,sizeof(seraddr));
        len=recvfrom(ser_sockfd,seraddr,sizeof(seraddr),,(struct sockaddr*)&ser_addr,&addrlen);
        /*显示client端的网络地址*/
        printf("receive from %s\n",inet_ntoa(ser_addr.sin_addr));
        /*显示客户端发来的字串*/
        printf("recevce:%s",seraddr);
        /*将字串返回给client端*/
        sendto(ser_sockfd,seraddr,len,,(struct sockaddr*)&ser_addr,addrlen);
    }
}

客户端：

/*
 *UDP/IP应用编程接口（API）
 *客户端的工作流程：首先调用socket函数创建一个Socket，填写服务器地址及端口号，
 *从标准输入设备中取得字符串，将字符串传送给服务器端，并接收服务器端返回的字
 *符串。最后关闭该socket。
 */
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<errno.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include <netinet/in.h>
#import <arpa/inet.h>
int GetServerAddr(char * addrname)
{
    printf("please input server addr:");
    scanf("%s",addrname);
    return ;
}
int main(int argc,char **argv)
{
    int cli_sockfd;
    int len;
    socklen_t addrlen;
    char seraddr[];
    struct sockaddr_in cli_addr;
    char buffer[];
    GetServerAddr(seraddr);
    /* 建立socket*/
    cli_sockfd=socket(AF_INET,SOCK_DGRAM,);
    if(cli_sockfd<)
    {
        printf("I cannot socket success\n");
        return ;
    }
    /* 填写sockaddr_in*/
    addrlen=sizeof(struct sockaddr_in);
    bzero(&cli_addr,addrlen);
    cli_addr.sin_family=AF_INET;
    cli_addr.sin_addr.s_addr=inet_addr(seraddr);
    //cli_addr.sin_addr.s_addr=htonl(INADDR_ANY);
    cli_addr.sin_port=htons();
    bzero(buffer,sizeof(buffer));
    /* 从标准输入设备取得字符串*/
    len=read(STDIN_FILENO,buffer,sizeof(buffer));
    /* 将字符串传送给server端*/
    sendto(cli_sockfd,buffer,len,,(struct sockaddr*)&cli_addr,addrlen);
    /* 接收server端返回的字符串*/
    len=recvfrom(cli_sockfd,buffer,sizeof(buffer),,(struct sockaddr*)&cli_addr,&addrlen);
    //printf("receive from %s\n",inet_ntoa(cli_addr.sin_addr));
    printf("receive: %s",buffer);
    close(cli_sockfd);
}