代码：      
/一个SOCKET程序的客户端
#include
#include
#include
#include
#include
#include
#include
#define PORT 9311
#define SRV_ADDR "172.20.11.10"
main()
{
        int sock_fd,len;
        char * msg;
        struct sockaddr_in srvaddr;
        srvaddr.sin_family=AF_INET;
        srvaddr.sin_port=htons(PORT);
        srvaddr.sin_addr.s_addr=inet_addr(SRV_ADDR);
        bzero(&(srvaddr.sin_zero));
        socket(AF_INET,SOCK_STREAM,0);
        if(sock_fd==-1)
        {
                printf("Create socket error !");
        exit(1);
        }
        connect(sock_fd,(struct sockaddr *)&srvaddr,sizeof(struct sockaddr));
        msg="你好，我在客户端向服务器问好！";
        len=strlen(msg);
        send(sock_fd,msg,len,0);
        close(sock_fd);
}

我用cc client.c命令编译后出现如下错误，
错误：
undefined                       first referenced
 symbol                             in file
htons                               client.o
inet_addr                           client.o
socket                              client.o
connect                             client.o
send                                client.o
i386ld fatal: Symbol referencing errors. No output written to a.out

恳请高人指点！小弟感激不尽！

cc client.c -lsocket