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  • DCFAQ: Check here first before asking!

    Please feel free to add to this thread with helpful info for others to share. This is intended for people have questions, and not to spread the sk disease. :)

  • #2
    QUESTION: How do I send and receive email via telnet?


    SMTP with telnet
    Copyright © 1999 Dru
    This mini-tutorial assumes that you are fimiliar with using the RFC editor and has an understanding of ports. There is a good newbie explanation of how ports work at (search for ports). In FreeBSD (as in most UNIX systems), /etc/services lists the well-known ports and other commonly used ports above 1024.

    This tutorial is useful for explaining the protocols at work in sending and receiving email. It is also a refreshing change for those who've always assumed that the bloat of a GUI email program was a mandatory part of the process. It can also prevent your email from piling up uncontrollably while you are still figuring out how to use sendmail and how to install qpopper!

    Email is sent with SMTP (defined in RFC 821) which has been assigned the well-known port 25. Knowing this, we can use Telnet to directly connect to, and place mail directly on, any mail server in the world. The only tools required are a telnet prompt (which is available on any OS that has TCP/IP installed) and a recipient's email address. No email program, text editor, or browser required.

    Let's say we want to send a message to At a command prompt simply type:

    telnet 25

    Don't forget the port number. If you don't specify the port number and the sysadmin has set up any security, you'll either get an access denied message or some sort of message stating your intrusion has been monitored. If you inadvertantly forget the port number and instead get a Connected to..... message, you've just broken into that server; hopefully, you are not using that company as your ISP!


    telnet 25
    After a moment you should get a response that includes the mail server's IP address, a Connected to message, followed by a line stating the mail program being used and the time.

    In telnet, success is noted by a line beginning with 2xx, failure by 5xx.

    To send your message:

    mail from: <youremailaddress>

    (wait for sender OK message)

    rcpt to: <>

    (wait for recipient OK message)


    (wait for Enter mail message)

    Then type in your message.
    You can type as many lines as you like
    As long as your very last line
    Is a period all by itself
    Like this:

    You will receive an OK message with a mail ID number

    leaves telnet

    One note about sending mail with telnet. If you try to place mail on a server with a different address than the recipient, you will receive a "We don't relay" message. So, if your recipient is, don't try to leave a message at

    There are some other SMTP commands that are usually disabled at the mail server as they invite malicious use. Again, if your ISP has not disabled these commands, I would consider finding another ISP.

    EXPN <anyname> will give the names of everyone in a mailing list

    VRFY <username> will give information on a particular user

    You'll notice in SMTP that there is no command to retreive mail. This is because POP is used to retreive and read email. Most mail servers and email programs use POP3 which is defined by RFC 1725 and uses port 110. Also notice that you do not need to login or provide any credentials to place a message on a mail server. This is mandatory to retreive email, so a USER and PASS command are defined in POP3.

    To read your email (for free, anywhere in the world, and with only a telnet prompt):

    telnet < 110> (wait for connect message)

    user <yourusername> (wait for confirmation)

    pass <yourpassword> (wait for confirmation)

    list (to view the number of messages)

    retr <messagenumber> (to read the message; FreeBSD's scroll buffer is very useful here)

    dele <messagenumber> (to delete the message)

    last (to get the last message number; useful for the forgetful who receive lots of email)

    quit (to leave telnet)



    • #3
      sk disease?


      • #4
        QUESTION: What is SK disease?

        Answer: Script Kiddie Disease.
        This is an affliction where a persona-non-technica is able to copy and paste and compile, or download the binary and use without knowing how the internals work, or what they are doing.

        This is prevented by giving enough detail to assist the person requesting help, but not all of the detail. Using mechanisms such as psuedo-code is a good example. Usually sk's will look for something easier to use than an explanatory tutorial.

        Kill your local sk today.


        • #5
          Ah, I see. well since I work with computer that do NOT have little pieces of bitten fruit on them, I know what I'm doing. :)


          • #6
            And a quick quiz question to derail this thread from it's topic.

            Why an apple with a bite taken out of it?
            "All the subtlety of a chainsaw,
            with none of the social graces."


            • #7
              Originally posted by R.J.
              Why an apple with a bite taken out of it?

              How did Apple get its name, and how did Apple get that logo?

              Steve Jobs had worked during the summer at an apple farm, and admired the Beatles' record label, Apple. He also believed Apples to be the most perfect fruit. He and Steve Wozniak were trying to figure out a name for their new company, and they decided that if they couldn't think of one by the end of the day that was better than Apple, they would choose Apple. They couldn't think of anything better, so on April 1, 1976, Apple Computer, Inc. was born.

              But they needed a logo. The first design included Sir Isaac Newton, a tree and a banner that said "Apple Computer." Jobs decided they needed a less busy logo, one that would signify a brand. The second logo attempt was very similar to the current logo, but without the bite taken out of it. Jobs thought this logo looked too much like an orange. The third attempt was the logo that Apple still uses.



              • #8
                Too bad he didn't live in Vegas across from the chicken ranch.


                • #9
                  Originally posted by astcell
                  Too bad he didn't live in Vegas across from the chicken ranch.

                  It certainly would have been an entirely different Silcon Valley... ?

                  <drummer in background, pah-dum-pmp+(cymbal crash)>