pop3c.c.zip

#include <stdio.h> #include <stdlib.h> #include <errno.h> #include <string.h> #include <netdb.h> #include <sys/types.h> #include <netinet/in.h> #include <sys/socket.h> #define POP3SERVPORT 110 #define MAXDATASIZE 512*1024 int main(int argc, char *argv[]) { int sockfd; struct hostent *host; struct sockaddr_in serv_addr; char *POPMessage[]={ "USER *******\r\n", "PASS *******\r\n", "STAT\r\n", //"LIST\r\n", "RETR 1\r\n", "QUIT\r\n", NULL }; int iLength; int iMsg=0; int iEnd=0; char buf[MAXDATASIZE]; /*if((host=gethostbyname("excnt0at.corp.good.com"))==NULL) { perror("gethostbyname error"); exit(1); }*/ if((host=gethostbyname("pop3.sina.com.cn"))==NULL) { perror("gethostbyname error"); exit(1); } if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) { perror("socket error"); exit(1); } serv_addr.sin_family=AF_INET; serv_addr.sin_port=htons(POP3SERVPORT); serv_addr.sin_addr = *((struct in_addr *)host->h_addr); bzero(&(serv_addr.sin_zero),8); if (connect(sockfd, (struct sockaddr *)&serv_addr,sizeof(struct sockaddr))==-1) { perror("connect error"); exit(1); } do { send(sockfd,POPMessage[iMsg],strlen(POPMessage[iMsg]),0); /*iLength=recv(sockfd,buf+iEnd,sizeof(buf)-iEnd,0); iEnd+=iLength; buf[iEnd]='\0';*/ printf("have sent: %s",POPMessage[iMsg]); if(iMsg == 3) { sleep(15); } else if(iMsg == 4) { sleep(10); } else { sleep(3); } iLength=recv(sockfd,buf,sizeof(buf),0); buf[iLength] = '\0'; printf("received length this time:%d\n",iLength); //printf("received: %s\n",buf+iEnd-iLength); printf("received: %s\n",buf); iMsg++; } while (POPMessage[iMsg]); close(sockfd); return 0; }