POINT A - sendfile.php
<?php
$postdata = 'file='.urlencode(file_get_contents('filetosend.txt'));
system('wget --post-data "'.$postdata.'" http://localhost/otherfile.php')
?>
According to that script the file contents of filetosend.txt are transferred VIA http post to http://localhost/otherfile.php
POINT B - otherfile.php
<?php
if (isset($_POST['file'])) {
file_put_contents('savehere.txt', $_POST['file']);
}
?>
According to that script the file contents are resaved in savehere.txt