ftp编程问题 USER PASS命令

blueskyww

ftp login代码段如下：
login()
{
.....
char buffer[256];
bzero(buffer,sizeof(buffer));
sprintf(buffer,"USER %s\r\n",user);
send(sock,buffer,sizeof(buffer),0);
recvbuff(sock);


sprintf(buffer,"PASS %s\r\n",pass);
send(sock,buffer,sizeof(buffer),0);
recvbuff(sock);

return 0;}


int recvbuff(int sock)
    {   
        char buff[1024];
        bzero(buff,1024); //清0
        int ret =  recv(sock,buff,1024,0);
        printf(buff);
        return 0;   
    }


结果是
control connect success.
220---------- Welcome to Pure-FTPd [TLS] ----------
220-You are user number 1 of 50 allowed.
220-Local time is now 13:58. Server port: 21.
220-IPv6 connections are also welcome on this server.
220 You will be disconnected after 15 minutes of inactivity.
331 User root OK. Password required
。。。。


谁可以帮忙分析哈是什么原因哦，万分感谢

blueskyww

系统是suse linux， pureftp
而且我直接登录用户名和密码都对，就是编程实现就有错了

blueskyww

会不会是pureftp的设置问题呢