Remote File Download to space using PHP

I just moved to the blog and planned to migrate the data in two spaces. But when something went wrong, I thought that PHP could remotely download files when the packaged files were too large.
Then I wrote a script!

01	<?php
02	if ($_GET[xfer]) {

 

03	if ($_POST[from] == "") {
04	print "You forgot to enter a url.";

 

05	} else {
06	copy("$_POST[from]", "$_POST[to]");

 

07	$size = round((filesize($_POST[to])/1000000), 3);
08	print "transfer complete.<br>

 

09	<a><a href=\"$_POST[from]\">$_POST[from]</a><br>
10	<a><a href=\"$_POST[to]\">$_POST[to]</a> : $size MB";

 

11	}
12	} else {

 

13	print "<form action=\"$PHP_SELF?xfer=true\" method=post>
14	Remote File (please include http: //): <input name = from> <br>

 

15	Save file name: <input name = to> <br>
16	<input type=submit value=\"transload\">";

 

17	}
18	?>

However, not all virtual hosts support this function. You have to check whether some functions are enabled. I don't know what functions are supported.