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#include<netdb.h>

#include<errno.h> #include<arpa/inet.h> #include<sys/stat.h> #include<unistd.h> #include<termios.h> #include <stdio.h> #include<strings.h> #include<string.h> struct sockaddr_in ftp_server; int sock_control; int sock_data; struct timeval outtime; int ret; char rcv_buff[1024]; int reply_code; int main() {   bzero(&ftp_server,sizeof(struct sockaddr_in));   ftp_server.sin_family=AF_INET;   ftp_server.sin_port=htons(21);   ftp_server.sin_addr.s_addr=inet_addr("127.0.0.1");   #if 1   //connec to ftp server.   sock_control=socket(AF_INET,SOCK_STREAM,0);   if(sock_control<0)   {     printf("create socket failed!\n");     return -1;   }   outtime.tv_sec=0;   outtime.tv_usec=300000;   ret=setsockopt(sock_control,SOL_SOCKET,SO_RCVTIMEO,&outtime,sizeof(outtime));   if(ret!=0)   {     printf("setsockopt failed!\n");     return -1;   }   if(connect(sock_control,(struct sockaddr *)&ftp_server,sizeof(struct sockaddr_in))<0)   {     return -1;   } #endif     //read server's reply.(welcome message). #if 1   ret=read(sock_control,rcv_buff,1024);   if(ret>0)   {     printf("read:@@ %s @@\n",rcv_buff);     reply_code=atoi(rcv_buff);     //continue to read the rest welcome message.     while(1)     {       rcv_buff[ret]='\0';       ret=read(sock_control,rcv_buff,1024);       if (ret<=0)       {     break;       }       printf("read:@@ %s @@\n",rcv_buff);     }   }   else   {     printf("read welcome message failed\n");     return -1;   } #endif #if 1   //ftp user login.   bzero(rcv_buff,sizeof(rcv_buff));   strcpy(rcv_buff,"USER shell.albert\r\n");   write(sock_control,rcv_buff,strlen(rcv_buff));   while(1)   {     bzero(rcv_buff,sizeof(rcv_buff));     ret=read(sock_control,rcv_buff,1024);     if(ret>0)     {       printf("read:@@ %s @@\n",rcv_buff);     }else{       break;     }   }   //PASS.   bzero(rcv_buff,sizeof(rcv_buff));   strcpy(rcv_buff,"PASS smartbean\r\n");   write(sock_control,rcv_buff,strlen(rcv_buff));   while(1)   {     bzero(rcv_buff,sizeof(rcv_buff));     ret=read(sock_control,rcv_buff,1024);     if(ret>0)     {       printf("read:@@ %s @@\n",rcv_buff);     }else{       break;     }   } #endif #if 1   //enter PASV(passive) mode.   bzero(rcv_buff,sizeof(rcv_buff));   strcpy(rcv_buff,"PASV\r\n");   write(sock_control,rcv_buff,strlen(rcv_buff));   bzero(rcv_buff,sizeof(rcv_buff));   while(1)   {     ret=read(sock_control,rcv_buff,1024);     if(ret>0)     {       printf("read:@@ %s @@\n",rcv_buff);     }else{       break;     }   }   //parse out the port number.P1*256+P2.   int nPasvPort;   char *sPasvPort=0;   sPasvPort=strrchr(rcv_buff,',');   if(sPasvPort==NULL)   {     printf("get pasv port1 error!\n");     return;   }   nPasvPort=atoi(sPasvPort+1);   *sPasvPort='\0';   sPasvPort=strrchr(rcv_buff,',');   if(sPasvPort==NULL)   {     printf("get pasv port2 error!\n");     return;   }   nPasvPort+=atoi(sPasvPort+1)*256;   printf("pasv port=%d\n",nPasvPort);     //use new port to connect server to get the data connection.   ftp_server.sin_port=htons(nPasvPort);   sock_data=socket(AF_INET,SOCK_STREAM,0);   if(sock_data<0)   {     printf("create socket failed!\n");     return -1;   }   outtime.tv_sec=0;   outtime.tv_usec=300000;   ret=setsockopt(sock_data,SOL_SOCKET,SO_RCVTIMEO,&outtime,sizeof(outtime));   if(ret!=0)   {     printf("setsockopt failed!\n");     return -1;   }   if(connect(sock_data,(struct sockaddr *)&ftp_server,sizeof(struct sockaddr_in))<0)   {     return -1;   }   printf("create data connection sucess!\n"); #endif   #if 1   //use PI(control channel) to send PWD command   //PWD's result was returned by PI.   bzero(rcv_buff,sizeof(rcv_buff));   strcpy(rcv_buff,"PWD\r\n");   write(sock_control,rcv_buff,strlen(rcv_buff));   bzero(rcv_buff,sizeof(rcv_buff));   while(1)   {     ret=read(sock_control,rcv_buff,1024);     if(ret>0)     {       printf("read:@@ %s @@\n",rcv_buff);     }else{       break;     }   } #endif   return 0; }