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baskuenen

How do I implement my own - Client SMTP eMail Connection...

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Here I go again with some stupid questions... My network knowledge is low, so please take it easy on me this time
Telnet and Hotmail:
  • Can I telnet to hotmail?
  • Can I simply use port 25?
  • Must I use http://www.hotmail.com or is myname@hotmail.com better?
  • Why doesn''t it still work?
  • SMTP client connection:
  • I already got the gethostbyname() and connect()
  • How do I send the subject and date?
  • Do I need to recv after a connect?
  • Do I need to recv() after each line send()?
  • I only want to send a single HTML page.
  • Is "Content-Type: text/html\r\n" all you need in the header?
  • Do I need an extra "\n" after the header before sending the HTML page?
  • It''s a lot of questions, so thanks already for reading them - Bas

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    Thanks Dak!

    After doing some more research, I came up with the folowing implementation:

        
    //----------------------------------------------------------------------------

    #include <stdio.h>
    #include <string.h>
    #include <windows.h>
    #include <winsock.h>
    //----------------------------------------------------------------------------

    #define SMTP_PORT 25
    #define MAXBUF 4096
    //---------------------------------------------------------------------------

    void send_smtpcmd(SOCKET sock, char *szCmd)
    {
    char szReply[MAXBUF];
    int iLen;
    send(sock, szCmd, strlen(szCmd), 0);
    iLen = recv(sock, szReply, MAXBUF, 0);
    szReply[iLen] = 0;
    printf(szReply);
    }
    //---------------------------------------------------------------------------

    main()
    {

    WORD wVersionRequested = MAKEWORD( 2, 0 );
    WSADATA wsa;
    if (WSAStartup(wVersionRequested , &wsa)!=0)
    { printf("Winsock Initialization failed.\n"); return -1;
    }

    SOCKET sock;
    if ((sock=socket(AF_INET,SOCK_STREAM,0))==INVALID_SOCKET)
    { printf("Can not create socket.\n"); return -1;
    }

    char *szSMTPServer = "www.hotmail.com";
    struct hostent *hs;
    if ((hs=gethostbyname(szSMTPServer))==NULL)
    { printf("Can not resolve specified host.\n"); return -1;
    }
    SOCKADDR_IN addr;
    addr.sin_family = AF_INET;
    addr.sin_port = htons(SMTP_PORT);
    memcpy((void *)&addr.sin_addr.s_addr, hs->h_addr, hs->h_length);

    if (connect(sock,(LPSOCKADDR)&addr,sizeof(addr))==SOCKET_ERROR)
    { printf("Can not connect to specified host.\n"); return -1;
    }

    char packetbuf[MAXBUF];
    recv(sock, packetbuf, MAXBUF, 0);
    printf("BANNER: %s\n", packetbuf);

    send_smtpcmd(sock, "MAIL FROM: <me@domain.web>\r\n");
    send_smtpcmd(sock, "RCPT TO: <baskuenen@hotmail.com>\r\n"); //can be repeated

    send_smtpcmd(sock, "DATA\r\n");
    send_smtpcmd(sock,
    "Subject: Test HTML mail.\r\n"
    "MIME-Version: 1.0\r\n"
    "Content-Type: text/html; \r\n"
    " charset=\"iso-8859-1\"\r\n"
    "Content-Transfer-Encoding: quoted-printable\r\n"
    ".\r\n");

    closesocket(sock);
    printf("Done.\n");
    return 0;
    }
    //------------------------------------------------------------------------------


    The problem is I get: "Can not connect to specified host."
    There''s something wrong with my connect. But what? I checked the IP-address, and it''s hotmail!
    Is it possible to connect to hotmail? Or must I use my provider orso?

    Help very much respected

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    Oke - found it - must use my provider address, but I really don't understand why?

    I still dont know how to make good headers (Subject: Content-Type: ...etc...)
    Does anyone know a good link to any lists with possible commands for this?

    Sorry for my stupid questions on this topic I myself must still get used to asking such stupid stupid stupid questions (normally they are only stupid )
    ...He can code a SMTP client, but doesn't know how to connect to the SMTP server...this must be a laugh for some of you...



    Edited by - baskuenen on July 24, 2000 11:26:21 PM

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