Introduction to UNIX

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Introduction to UNIX

• I.Using Electronic Mail

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Introduction to Electronic Mail

• Performance Objectives
• 1. Describe basic E-mail concepts and etiquette
• 2. Describe the use of a mailserver
• 3. Locate your mailbox (/var/spool/mail)
• 4. Identify mail facilities
• (/usr/bin/mail, Pine, Eudora, Netscape
  mail, Outlook)
• 5. Parse an Internet E-mail domain address
• 6. Identify primary mail functions
• (read, send, delete, save, reply)

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E-Mail Concepts

• Use E-Mail to exchange information with users on
  the same or other
• Although E-Mail appears instantaneous,
• Messages may not be immediately posted to a
  recipient, or
• Recipient may not be logged on to the system, or
• may be busy with other tasks.

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Effective use of E-Mail

• Choose your words carefully.
• Log on at least once each day to read mail.
• Compose single-subject messages if possible.
• Define appropriate "subject" line - avoid "FYI"!
• Assume any message sent lives-on indefinitely.

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Effective use of E-Mail (cont)

• Know your intended audience
• Establish appropriate level of formality
• Keep list of recipients and CCs to a minimum.
• Identify yourself and your affiliations clearly.
• Know when NOT to use E-Mail
• Consider face-to-face, phone, paper and etc.

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E-Mail Functionality

• Receive and read mail
• Create and reply to mail
• Save, delete, or hold incoming mail
• Establish distribution lists
• Forward E-Mail to others
• Assume an alias to another account
• Provide travel/vacation advisement
• Find E-Mail Addresses

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How E-Mail is Routed

• E-Mail is sent to a central mailhost through a
  mailserver.
• Address determines internal/external route.
• Mail forwarded to destination mailserver
  (domain/host).
• Mail facility used to access.

Workstation
External gateway
Mailserver
Mailhost
Mailserver
Workstation
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UNIX Mail Facilities

• UNIX/SMTP (Simple Mail Transfer Protocol)
• mail (or sometimes mailx) - line oriented, can
  run on any terminal
• Pine, Elm - screen oriented, needs a
  cursor-addressable screen like VT100
• Macintosh/Windows
• Eudora - POP (Post Office Protocol) client,
  requires POP server
• Others

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Locating Your Mailbox

• Mail received by a server is usually
• stored in
• /var/spool/mail/userid
• host ls -l /var/spool/mail/ths
• 256 -rw------- 1 ths 248615 Apr 25 1150
  /var/spool/mail/ths

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E-Mail Addresses

• Usually a multi-part format
• abc_at_lanl.gov
• Additional hosts may be included
• abc_at_hr.div1.stanford.edu

Domain
Host
User
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Forwarding E-Mail

• Most mail services allow forwarding.
• Several systems on which you receive mail
• One preferred to read and log your mail.
• Set forwarding flag on those you do not want to
  read mail.
• UNIX home directory labeled .forward.
• Contains address where you read your mail.

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Forked Mail

• POP Servers permit "forked" mail
• Keeps a copy of each message
• Forwards a copy to another address
• Put addresses in the .forward file
• \chtxxxxx (Account to keep a copy)
• def_at_lanl.gov (Address to forward a copy)

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Attachments

• Most E-Mail systems communicate using ASCII
  character sets.
• Binary data or formatted data may have to be sent
  using uuencode or binhex or mime.
• Some mail readers cannot process these files.
• Avoid sending anything but ASCII files unless you
  know that your recipient can handle them.

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End of Module