I gone through couple of sources and wrote the below code.
It works perfectly for me.
export ATTACHMENT=/x/project/Emp_Report.xlsx
EMAIL_BOUNDARY_STRING=Z${RANDOM}${RANDOM}${RANDOM}${RANDOM}
if [[ -f /x/project/Emp_Report.xlsx ]]; then
echo "Employee Report exists !!"
(
echo "From: abc@gmail.com"
echo "To: xyz@gmail.com"
echo "cc: pqr@gmail.com"
echo "Subject:Employee Report"
echo "MIME-Version: 1.0"
echo 'Content-Type: multipart/mixed; boundary="${EMAIL_BOUNDARY_STRING}"'
echo '--${EMAIL_BOUNDARY_STRING}'
echo "Content-Type: text/html"
echo "Content-Disposition: inline"
echo "<html>"
echo "<body>"
echo "<p>Hi Team,</p>"
echo "<p>Please find the Employee details in attachment.</p>"
echo "<p>In case of any queries, kindly reach out to 'abc@gmail.com'</p>"
echo "<b>Regards,</b><br>"
echo "Abc"
echo "</body></html>"
echo '--${EMAIL_BOUNDARY_STRING}'
echo 'Content-Type: application/octet-stream; name="'$(basename $ATTACHMENT)'"'
echo "Content-Transfer-Encoding: base64"
echo 'Content-Disposition: attachment; filename="'$(basename $ATTACHMENT)'"'
uuencode -m $ATTACHMENT $(basename $ATTACHMENT)
) | /usr/sbin/sendmail -t
