In this post I'm going to show how to send an email from the Linux command line through your Gmail account. This can be handy if you're a command line junkie. The real power, however, is in being able to send an email automatically from a script. I'll be doing another post where I use this in a script to notify me when something has changed on my system. For now though, I'll just show the setup so you can send an email from the command line. This process has been tested on Ubuntu 12.04 and Linux Mint 13.
First off, I must acknowledge that I did not figure this out on my own. Ubuntu Forums member, Stephen Morgan, showed how to do it here.
The first step is to install the msmtp-mta package.
After the install is complete you'll need to set up the defaults file with your Gmail account information. You need to create a file in your home directory called .msmtprc.
Paste the following into the file and edit the portions in bold to reflect your account information.
account default : gmail
Save the file and exit the text editor. Since this file contains your account credentials, you'll want to change the permissions to make the file readable only by you.
Now that your computer is configured to talk to Gmail, you need a command line email program to handle writing your email. For this I'm going to use mailx from the heirloom-mailx package.
Now you need to set up the defaults file so that mailx uses msmtp to send out the email. This file is called .mailrc.
Now paste the following into the file and save it.
set message-sendmail-extra-arguments="-a gmail"
You should now be able to send email from your terminal command line.
Sending email from the command line
Now you can send email from the command line like this:
The cursor will go to a blank line. Enter your email message. When you're done, hit <Enter> to go to a blank line and then hit <Ctrl>+D to end your message. You have just sent your email.
Here you can see that I've sent an email to myself from my Gmail account.
You can also use a message saved in a text file rather than entering it interactively. This is especially useful if you're automating this process in a script. In this example, the email is saved in a file called message.txt.
This content originally appeared at http://tuxtweaks.com/2012/10/send-gmail-from-the-linux-command-line/.