To clarify the intent of my question, let me make an analogy to the question "What is the simplest way to put data into a file?"
The usual way that GUI users will put data into a (new) file is to double click on a program icon, click the menu bar, click "new," click "save," click to choose a location for the file, type the name of the file, and click the "save" button.
The simplest way to put data into a file (from the command line) is: echo whatever > file
As I understand it, email addresses originally referred to actual usernames on machines and actual machine names. So if the IP of the machine you logged into (say, at a university) was 7.7.7.7, and if you logged in with the username pete
, you could be reached by email sent to [email protected]
. (Is that right?)
The point is that the email was directly associated with your user name and computer. Hence why an email I received from the command line of a server at work showed as sent from "[email protected]".
So, what is the minimal setup needed to send and receive email between two computers (directly to command line user accounts), with no third computer or Google server or MS Exchange or whatever else?
(For UNIX and Linux systems, obviously. Mostly interested in Linux, though if Mac is included that would be nice.)
Note: If there are a huge number of different ways to do it so this is "too broad," please help me edit the question. I'm not asking for software recommendations, I'm asking for how the parts fit together at the simplest level without proxies and relays and other complexities.
Edit: The answers so far are helpful but omit any details on how to receive the email. It seems that the Google search phrase I was missing is "minimal MTA Linux" but if anyone would like to answer more fully I would love it. (If not I'll have to work it out and eventually self-answer.) :)
bigvax
your email address would have beenbigvax!pete
. Unfortunately there wasn't a central database of hostnames so you had to provide a path that would tell the mailers how to get the message to you. Lots of history there - look up uucp bang paths