install

apt-get install ssmtp
apt-get install mailutils

configure

edit /etc/ssmtp/ssmtp.conf:

root=
mailhub=mail.net-c.com:465
hostname=myhost.com
AuthUser=usermail@netc.fr
AuthPass=ENTER-SMTP-PASSWORD-HERE
FromLineOverride=YES
UseTLS=YES

Test

echo "Hello world email body" | mail -s "Test Subject" test@mail.fr