#!/usr/bin/perl

use strict;
use warnings;

my $sendmail_path = '/usr/sbin/sendmail'; # or whatever the path to sendmail is
my $to = 'test@test.example'; # your own mail address
my $from = 'test2@test.example';
my $subject = 'Test';
my $body = 'Testnachricht';

open MAIL, "| $sendmail_path -oi -t" or die $!;
print MAIL qq~To: $to
From: $from
Subject: $subject

$body~;
close MAIL;