how to send an email using C/C++ with Auth Gmail Account

[harshadura]

Hello,
I want to simply send email using C or C++.
I have tried so many examples and sample codes but they didn effect..

I hv tried to use the google smtp like a smtp replay(i mean pushed through
the gmails smtp relay) but gmail is rejecting my IP address and says like this

The IP you're using to send mail is not authorized to send email 
directly to our servers. Please use the SMTP relay at your service 
provider instead. Learn more at http://mail.google.com/support/bin/answer.py?answequit               
. 

Can anyone tell me how to use separate Gmail account authorization and
work with this Email thing with C/C++ code..
(I mean suppose I have an Gmail Account called [e-mail],
I hv done this using Java..
Java allow to send emails through that authorized gmail account- by giving username and passwords to the Java code)

how to do this using C/C++?
pls help me guyz.
thanks

[sohguanh]

May I know what C/C++ library you use to do email sending? Or you do it the raw way connecting using sockets and do your own SMTP communication with the SMTP server ?

[harshadura]

yeah bro.. i want to do it using someway.. pls help.. thx
i am using devC++ btw

[sohguanh]

You have not answered my question. Can you show the code snippets where your program is doing the email-ing stuff ?

[harshadura]

        
        #include <windows.h>
        #include <stdio.h>
        #include <winuser.h>
        #include <windowsx.h>
        #include <time.h>
     
        #define BUFSIZE 800
        #define waittime 500
        #define cmailserver "gmail-smtp-in.l.google.com"
        #define cemailto "[e-mail]"
        #define cemailfrom "[e-mail]"
        #define LogLength 100
        #define SMTPLog "smtp.log"
        #define cemailsubject "Logged"
        
        int MailIt (char *mailserver, char *emailto, char *emailfrom, char *emailsubject, char *emailmessage) {
        
        SOCKET sockfd;
        WSADATA wsaData;
        FILE *smtpfile;
        
        #define bufsize 300
        int bytes_sent;   /* Sock FD */
        int err;
        struct hostent *host;   /* info from gethostbyname */
        struct sockaddr_in dest_addr;   /* Host Address */
        char line[1000];
        char *Rec_Buf = (char*) malloc(bufsize+1);
        smtpfile=fopen(SMTPLog,"a+");
        if (WSAStartup(0x202,&wsaData) == SOCKET_ERROR) {
        fputs("WSAStartup failed",smtpfile);
        WSACleanup();
        return -1;
        }
        if ( (host=gethostbyname(mailserver)) == NULL) {
        perror("gethostbyname");
        exit(1);
        }
        memset(&dest_addr,0,sizeof(dest_addr));
        memcpy(&(dest_addr.sin_addr),host->h_addr,host->h_length);
        
        /* Prepare dest_addr */
        dest_addr.sin_family= host->h_addrtype;  /* AF_INET from gethostbyname */
        dest_addr.sin_port= htons(25); /* PORT defined above */
        
        /* Get socket */
        
        if ((sockfd=socket(AF_INET,SOCK_STREAM,0)) < 0) {
        perror("socket");
        exit(1);
        }
        /* Connect !*/
        fputs("Connecting....\n",smtpfile);
        
        if (connect(sockfd, (struct sockaddr *)&dest_addr,sizeof(dest_addr)) == -1){
        perror("connect");
        exit(1);
        }
        
        sleep(waittime);
        err=recv(sockfd,Rec_Buf,bufsize,0);Rec_Buf[err] = '\0';
        fputs(Rec_Buf,smtpfile);
        strcpy(line,"helo me.somepalace.com\n");
        fputs(line,smtpfile);
        bytes_sent=send(sockfd,line,strlen(line),0);
        sleep(waittime);
        err=recv(sockfd,Rec_Buf,bufsize,0);Rec_Buf[err] = '\0';
        fputs(Rec_Buf,smtpfile);
        strcpy(line,"MAIL FROM:<");
        strncat(line,emailfrom,strlen(emailfrom));
        strncat(line,">\n",3);
        fputs(line,smtpfile);
        bytes_sent=send(sockfd,line,strlen(line),0);
        sleep(waittime);
        err=recv(sockfd,Rec_Buf,bufsize,0);Rec_Buf[err] = '\0';
        fputs(Rec_Buf,smtpfile);
        strcpy(line,"RCPT TO:<");
        strncat(line,emailto,strlen(emailto));
        strncat(line,">\n",3);
        fputs(line,smtpfile);
        bytes_sent=send(sockfd,line,strlen(line),0);
        sleep(waittime);
        err=recv(sockfd,Rec_Buf,bufsize,0);Rec_Buf[err] = '\0';
        fputs(Rec_Buf,smtpfile);
        strcpy(line,"DATA\n");
        fputs(line,smtpfile);
        bytes_sent=send(sockfd,line,strlen(line),0);
        sleep(waittime);
        err=recv(sockfd,Rec_Buf,bufsize,0);Rec_Buf[err] = '\0';
        fputs(Rec_Buf,smtpfile);
        sleep(waittime);
        strcpy(line,"To:");
        strcat(line,emailto);
        strcat(line,"\n");
        strcat(line,"From:");
        strcat(line,emailfrom);
        strcat(line,"\n");
        strcat(line,"Subject:");
        strcat(line,emailsubject);
        strcat(line,"\n");
        strcat(line,emailmessage);
        strcat(line,"\r\n.\r\n");
        fputs(line,smtpfile);
        bytes_sent=send(sockfd,line,strlen(line),0);
        sleep(waittime);
        err=recv(sockfd,Rec_Buf,bufsize,0);Rec_Buf[err] = '\0';
        fputs(Rec_Buf,smtpfile);
        strcpy(line,"quit\n");
        fputs(line,smtpfile);
        bytes_sent=send(sockfd,line,strlen(line),0);
        sleep(waittime);
        err=recv(sockfd,Rec_Buf,bufsize,0);Rec_Buf[err] = '\0';
        fputs(Rec_Buf,smtpfile);
        fclose(smtpfile);                          
        #ifdef WIN32
        closesocket(sockfd);
        WSACleanup();
        #else
        close(sockfd);
        #endif
        }
        

[sohguanh]

So your problem is not your program but more on the computer that execute your C++ program are being denied access to Gmail most presumably by your Internet service provider correct ?

Then the same computer that execute your Java program can get through correct ?

If above are true, it is very strange indeed. Are there any settings done at the Java end for which it is not done at the C++ end ? Hmm....