By using Atom feeds you can able to view your unread mails in gmail using terminal in ubuntu.
Open Terminal
Install Curl
sudo apt-get install curl
then use the following command line
curl -u username –silent “https://mail.google.com/mail/feed/atom” | perl -ne ‘print “\t” if //; print “$2\n” if /(.*)/;’
replace user name with your gmail account
Now it will ask you for password
enter the password you will be able to see your unread mails
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