#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <unistd.h>
#include <arpa/inet.h>

#define MAXBUF 1024

int main(int argc, char *argv[])
{
    int pid;	
    int sockfd, new_fd;
    socklen_t len;
    struct sockaddr_in my_addr, their_addr;
    unsigned int myport, lisnum;
    char buf[MAXBUF + 1];

    if (argv[2])
    myport = atoi(argv[2]);    // 将命令行字符串转换为整数
    else
    myport = 7575;      // 默认设置端口大小

    if (argv[3])
    lisnum = atoi(argv[3]);  // 监听队列大小
    else
    lisnum = 5;       // 默认大小

    if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1)  // 创建socket对象
    {
        perror("socket");
        exit(EXIT_FAILURE);
    }

    bzero(&my_addr, sizeof(my_addr));
    my_addr.sin_family = AF_INET;         // 地址协议
    my_addr.sin_port = htons(myport);      // 地址端口
    if (argv[1])      // 点分十进制字符串转换为网络序的IP地址
    my_addr.sin_addr.s_addr = inet_addr(argv[1]);  
    else
    my_addr.sin_addr.s_addr = INADDR_ANY;      // 设置本地任意地址

    if (bind(sockfd, (struct sockaddr *) &my_addr, sizeof(struct sockaddr))== -1)  
    {               // 绑定信息
        perror("bind");
        exit(EXIT_FAILURE);
    }

    if (listen(sockfd,lisnum ) == -1)  // 监听网络
    {
        perror("listen");
        exit(EXIT_FAILURE);
    }
    printf("wait for connect\n");	 // 提示信息:等待连接
    len = sizeof(struct sockaddr);
    if ((new_fd =accept(sockfd, (struct sockaddr *) &their_addr,&len)) == -1)  // 接受连接 ,阻塞方式
    {
        perror("accept");
        exit(EXIT_FAILURE);
    } 
    else
printf("server: got connection from %s, port %d, socket %d\n",inet_ntoa(their_addr.sin_addr),ntohs(their_addr.sin_port), new_fd);        // 输出信息

    if(-1==(pid=fork()))	// 创建子进程
    {
        perror("fork");exit(EXIT_FAILURE);
    }
    else if( pid == 0)       // 不停的发送信息
    {
        while (1) 
        {
            bzero(buf, MAXBUF + 1);
            printf("input the message to send:");
            fgets(buf, MAXBUF, stdin);
            if (!strncasecmp(buf, "quit", 4)) 
            {
                printf("i will close the connect!\n");
                break;
            }
            len = send(new_fd, buf, strlen(buf) - 1, 0);
            if (len < 0)
            {
                printf("message'%s' send failure!errno code is %d,errno message is '%s'\n",
                       buf, errno, strerror(errno));
                break;
            }
        }
    }
    else 
    {	
        while(1)                 // 父进程接受信息
        {
            bzero(buf, MAXBUF + 1);
            len = recv(new_fd, buf, MAXBUF, 0);
            if (len > 0)
            printf("message recv successful :'%s',%dByte recv\n",buf, len);
            else if (len < 0)
            {
                printf("recv failure!errno code is %d,errno message is '%s'\n",
                       errno, strerror(errno));
                break;
            }
            else
            {
                printf("the other one close quit\n");
                break;
            }
        }
    }
    close(new_fd);
    close(sockfd);
    return 0;
}

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <sys/socket.h>
#include <resolv.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>

#define MAXBUF 1024

int main(int argc, char **argv)
{
    int sockfd, len;
    struct sockaddr_in dest;
    char buffer[MAXBUF + 1];
    if (argc != 3)     // 参数检查
    {
        printf(" error format,it must be:\n\t\t%s IP port\n",argv[0]);
        exit(EXIT_FAILURE);
    }

    if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)   // 创建socket对象
    {  
        perror("Socket");
        exit(errno);
    }
    printf("socket created\n");

    bzero(&dest, sizeof(dest));
    dest.sin_family = AF_INET;    // 地址协议
    dest.sin_port = htons(atoi(argv[2]));  // 对方端口
    if (inet_aton(argv[1], (struct in_addr *) &dest.sin_addr.s_addr) == 0)  // 对方ip
    {
        perror(argv[1]);	exit(errno);
    }
    if (connect(sockfd, (struct sockaddr *) &dest, sizeof(dest))==-1)  // 发起连接
    {
        perror("Connect ");
        exit(errno);
    }
    printf("server connected\n");

    pid_t pid;
    if(-1==(pid=fork()))                   // 创建子进程
    {
        perror("fork");exit(EXIT_FAILURE);
    }
    else if (pid==0)     // 子进程接收数据
    {
        while (1) 
        {
            bzero(buffer, MAXBUF + 1);
            len = recv(sockfd, buffer, MAXBUF, 0);
            if (len > 0)
            printf("recv successful:'%s',%d byte recv\n",buffer, len);
            else if(len < 0)
            {
                perror("recv");
                break;
            }
            else
            {
                printf("the other one close ,quit\n");
                break;
            }
        }	
    }
    else           // 父进程发送数据
    {
        while (1) 
        {
            bzero(buffer, MAXBUF + 1);
            printf("pls send message to send:");
            fgets(buffer, MAXBUF, stdin);
            if (!strncasecmp(buffer, "quit", 4)) 
            {
                printf(" i will quit!\n");
                break;
            }
            len = send(sockfd, buffer, strlen(buffer) - 1, 0);
            if (len < 0) 
            {
                perror("send");
                break;
            }
        }
    }
    close(sockfd);
    return 0;
}