MSMTP is a SMTP client; it can be installed in the Linux Ubuntu with the following steps:
1. ~$ sudo apt-get install msmtp
2. ~$ vim .msmtprc # enter following lines
defaults
# zoho account (I am using my zoho email account)
account zoho
auth on
host smtp.zoho.com
port 465
user <user id here; most likely an email id>
password <password to log into email account>
from <email id here; most likely same as user id above>
tls on
tls_starttls off
tls_trust_file /etc/ssl/certs/ca-certificates.crt
# set default account to use
account default : zoho
# press ESC; then :wq! to save and exit from vim editor
3. ~$ chmod 600 .msmtprc
4. ~$ msmtp <to_email_id here> # leave a blank line after Subject as shown, else email won't work
Subject: Test mail
hello
# Ctrl-D to send
# check email received at to_email_id
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