I have a google mail account, so I am focussing only on accessing the google mail (gmail).
Below I will assume my google mail user has the following 'properties':
Disclaimer: I have no experience with setting up all this email stuff, so there might be better ways of doing this. What I did is based on a lot of googling.
I asked on the arduino forum for some pointers. I got a suggestion to look into the google python API's, but I got the impression that this is not for free at some point. So I abandoned that route.
I started reading about linux mail 'clients'. I learned a lot of things. I now know more or less what an MTA, MDA, MUA, etc... is :-)
I had no idea if I should use POP3 or IMAP. I went for POP3 for now. So first thing to do is to enable POP3 in your google account (I assume you know how to do this).
Next steps are on the arduino Yun:
login as root and run the following commands:
opkg update opkg install openssl-util opkg install fetchmail opkg install procmail opkg install shadow-useradd
This installs the packages that I think I will need.
I wasn't sure if I should eventually run my app as root, or if I can do it as another user.
I will give it a try as non-root. I decided to create a user called MrYafa:
mkdir /home useradd -m -c "Mr Yafa" MrYafa passwd MrYafa
Maybe the first command isn't needed. In the last command you obviously need to choose a password.
Then edit the /etc/passwd file (e.g vi /etc/passwd - I will assume you know how to work with vi)
You should see the newly created user. At the end of that line add /bin/ash
Now exit as root and try to login as MrYafa:
(on windows you might need to enter the IP address as arduino.local might not work)
You should be able to login an arrive in your home directory.
now create a file .fetchmailrc in that directory (vi .fetchmailrc) containing:
poll pop.gmail.com with proto pop3 user "email@example.com" there with password "mypassword" is "MrYafa" here mda "/usr/bin/procmail -d %T" options ssl
Now, if you give the command
you should see the communication with your google mail on the screen, ending with (in my case):
fetchmail: POP3> QUIT fetchmail: POP3< +OK Farewell. fetchmail: 6.3.26 querying pop.gmail.com (protocol POP3) at Wed, 30 Oct 2013 18:51:33 +0100 (CET): poll completed fetchmail: normal termination, status 1
That's it for now. Not so difficult when you know what to do, but it took a while to find that out.