Use MIME::Tools.
In particular try:

use strict;
use MIME::Parser; 
my $parser = new MIME::Parser;
$parser->output_under("./"); #directory where to store the components
my $entity = $parser->parse(\*STDIN) or die "parse failed\n";
$entity->dump_skeleton;
[download]

and from the console, write:

$perl abovecode.pl < mail.txt
[download]

So in ./ you'll find a directory like "msg-10237 (cut) 2055-0" in which you have the components.