client.c

为一个单进程循环的c/s服务器

/***************************************************************************
*    Copyright (C) 2006 by Soasen Co.,Ltd.   *
*    desc: 　CS模式通用客户端
*    座友铭：凡是程序当前不需要的，都是垃圾，80%的时间做20%的事情。（程序的效率）
*                                                                         *
***************************************************************************/
#include	<sys/types.h>
#include	<sys/socket.h>
#include	<netinet/in.h>
#include	<arpa/inet.h>
#include	<netdb.h>
#include	<stdio.h>
#include	<unistd.h>
#include	<errno.h>
#include    <string.h>
#include	<stdlib.h>

#define	MAXDATASIZE	1024

void process(FILE *fp,int sockfd);

int main(int argc,char *argv[])
{
    int sd,rc,i;
    struct sockaddr_in localAddr,servAddr;
    struct hostent *h;
    int	port;

    if(argc!=3)
    {
        printf("usage: %s<server><IP>\n",argv[0]);
        exit(1);
    }
    h=gethostbyname(argv[1]);
    if(h==NULL)
    {
        printf("%s:unknown host'%s'\n",argv[0],argv[1]);
        exit(1);
    }
    if((port=atoi(argv[2]))<0) 
    { 
        fprintf(stderr,"Usage:%s portnumber\a\n",argv[0]); 
        exit(1); 
    } 

    servAddr.sin_family=h->h_addrtype;
    memcpy((char *)&servAddr.sin_addr.s_addr,h->h_addr_list[0],h->h_length);
    servAddr.sin_port=htons(port);

    sd=socket(AF_INET,SOCK_STREAM,0);
    if(sd<0)
    {
        perror("cannot open socket");
        exit(1);
    }


    /*绑定端口号*/
    localAddr.sin_family=AF_INET;
    localAddr.sin_addr.s_addr=htonl(INADDR_ANY);
    localAddr.sin_port=htons(0);

    rc=bind(sd,(struct sockaddr *)&localAddr,sizeof(localAddr));
    if(rc<0)
    {
        printf("%s:cannot bind port TCP %d\n",argv[0],port);
        perror("error");
        exit(1);
    }

    /*连接到服务器*/
    rc=connect(sd,(struct sockaddr *)&servAddr,sizeof(servAddr));
    if(rc<0)
    {
        perror("cannot connect");
        exit(1);
    }


    process(stdin,sd);
    close(sd);
}

void process(FILE *fp,int sockfd)
{
    char sendline[MAXDATASIZE],revline[MAXDATASIZE];
    int numbytes;
    printf("Connetc to server:\n");

    while(fgets(sendline,MAXDATASIZE,fp)!=NULL){
        send(sockfd,sendline,strlen(sendline),0);
        if((numbytes=recv(sockfd,revline,MAXDATASIZE,0))==0){
            printf("server termined.\n");
            return;
        }
        revline[numbytes]='\0';
        printf("recv message:%s\n",revline);
    }
}