#!/usr/bin/perl
use warnings;
use strict;
use IPC::Open3;
use Tk;

my $mw=tkinit;

my $start_but = $mw->Button(-text => 'Start Scan',
            -command => \&start_scan)->pack();
	    
my $cancel_but = $mw->Button(-text => 'Cancel Scan',
            -command => \&stop_scan)->pack();	    

MainLoop;
###################################
sub start_scan{

# do a 'scanimage -L ' for your list
my @options = ( '-d umax:/dev/scanner', 
                '-b', 
		'--format=tiff',  
		'--batch-count=3',
		'--batch-prompt',
		);

#interface to scanimage
my $pid = open3(\*WRITE, 0 ,\*ERROR, "scanimage @options" );

$mw->fileevent('ERROR', 'readable' => \&collect_stderr); 
}

###############################################################
sub collect_stderr {  
   my $err = <ERROR>;     
        print  $err; 
    }  
###############################################################
sub stop_scan{
    #    print WRITE chr(4),"\n";
    #    print WRITE "\x04\n";
        print WRITE "\cd";
    #    print WRITE "\004\n"; 
}