Unix 网络编程第一章的demo

linux 下gcc编译通过
客户端

#include <unistd.h>  
#include <sys/types.h>  
#include <sys/socket.h>  
#include <netdb.h>  
#include <stdio.h>  
#include <stdlib.h>  
#include <string.h>  
#include <ctype.h>  
#include <errno.h>  
#include <stdlib.h>
#include <netinet/in.h>  
#include <arpa/inet.h>  
#include <sys/ioctl.h>  
#include <stdarg.h>  
#include <fcntl.h>  
#include <fcntl.h>  

#define MAXLINE 100

#define SA struct sockaddr

#define err_sys(info)  do{  printf("%s\n",info); exit (-1);} while(0)
int Socket(int family,int type,int protocol)
{
    int n;

    if((n=socket(family,type,protocol))<0)
        err_sys("socket error");
    return (n);
}

int Connect(int sockfd, struct sockaddr * serv_addr, int addrlen)
{
    int n;

    if((n=connect(sockfd,serv_addr,addrlen))<0)
        err_sys("connect error");
    return (n);
}
int main(int argc, char const *argv[])
{
    int sockfd,n;
    char recvline[MAXLINE+1];

    struct sockaddr_in servaddr;

    if(argc!=2)
    {
        printf("usage::thisprogram <IPaddress>\n");
        exit(-1);
    }


    sockfd=Socket(AF_INET,SOCK_STREAM,0);

    bzero(&servaddr,sizeof(servaddr));  //替代memset，对结构体进行初始化
    servaddr.sin_family=AF_INET;
    servaddr.sin_port=htons(13);
    if(inet_pton(AF_INET,argv[1],&servaddr.sin_addr)<=0)
    {
        printf("switch error\n");
        exit(-1);
    }

    Connect(sockfd,(SA *)&servaddr,sizeof(servaddr));

    while((n=read(sockfd,recvline,MAXLINE))>0)
    {
        recvline[n]=0;
        if(fputs(recvline,stdout)==EOF)
            err_sys("fputs error");

    }
    exit (0);

}

服务端

#include <unistd.h>  
#include <sys/types.h>  
#include <sys/socket.h>  
#include <netdb.h>  
#include <stdio.h>  
#include <stdlib.h>  
#include <string.h>  
#include <ctype.h>  
#include <errno.h>  
#include <stdlib.h>
#include <netinet/in.h>  
#include <arpa/inet.h>  
#include <sys/ioctl.h>  
#include <stdarg.h>  
#include <fcntl.h>  
#include <fcntl.h>  
#include <time.h>

#define MAXLINE 500

#define SA struct sockaddr

#define LISTENQ 10

#define err_sys(info)  do{  printf("%s\n",info); exit (-1);} while(0)

int Socket(int family,int type,int protocol)
{
    int n;

    if((n=socket(family,type,protocol))<0)
        err_sys("socket error");
    return (n);
}

int Bind(int sockfd, struct sockaddr * my_addr, int addrlen)
{
    int n;

    if((n=bind(sockfd,my_addr,addrlen))<0)
        err_sys("bind error");
    return (n);

}
int Listen(int s, int backlog)
{
    int n;

    if((n=listen(s,backlog))<0)
        err_sys("listen error");
    return (n);
}
int Accept(int s, struct sockaddr * addr, int * addrlen)
{
    int n;

    if((n=accept(s,addr,addrlen))<0)
        err_sys("accept error");
    return (n);

}
int Write(int fd,const void * buf,size_t count)
{
    int n;
    if((n=write(fd,buf,count))<0)
        err_sys("write error");
    return (n);

}
int Close(int fd)
{
    int n;
    if((n=close(fd))<0)
        err_sys("close error");
    return (n);
}

int main(int argc, char const *argv[])
{
    int listenfd,connfd;
    struct sockaddr_in servaddr;
    char buf[MAXLINE];
    time_t ticks;

    listenfd=Socket(AF_INET,SOCK_STREAM,0);
    bzero(&servaddr,sizeof(servaddr));
    servaddr.sin_family=AF_INET;
    servaddr.sin_addr.s_addr=htonl(INADDR_ANY);
    servaddr.sin_port=htons(13);

    Bind(listenfd,(SA *)&servaddr,sizeof(servaddr));

    Listen(listenfd,LISTENQ);

    for( ; ; )
    {
        connfd=Accept(listenfd,(SA *)NULL,NULL);

        ticks=time(NULL);

        snprintf(buf,sizeof(buf),"%.24s\r\n",ctime(&ticks));
        Write(connfd,buf,strlen(buf));

        Close(connfd);

    }




}