#!/usr/local/bin/perl
use MIME::Parser;
use strict;
use warnings;

## directory to store all parsed MIME parts
my $outputdir = "./mimemail";
my $parser = new MIME::Parser;
$parser->output_dir($outputdir);

## this creates files for all parts
my $entity = $parser->read(\*STDIN);
my $num_parts = $entity->parts;

## define attachment types to keep -- notice all lowercase
## add as many types as you like.
my %type_ok = (
   'application/octet-stream' => 1
);

if ($num_parts > 0) {
    for (my $i = 0; $i < $num_parts; $i++) {
        my $part = $entity->parts($i);
        ## note: lc so types have a better chance of matching
        my $type = lc $part->mime_type;
        my $bh = $part->bodyhandle;
        ## delete parts we don't want
        if (! exists $type_ok{$type}) {
           my $status = system("rm '$bh->{MB_Path}'");
           die $! unless $status == 0;
        }
    }
}