#!/usr/bin/perl -w
use strict;

sub CopyFileProgress ( ) {
	my	$src 	= shift;
	my	$dst		= shift;
	my	$callback	= shift;
	my	$num_read;
	my	$num_wrote;
	my	$buffer;
	my	$perc_done = 0;
	
	open (SRC, "< $src") or die "Could not open source file [$src]: $!\n";
	open (DST, "> $dst") or die "Could not open destination file [$dst]: $!\n";
	binmode SRC;
	binmode DST;
	
	my 	$filesize	= (-s $src) or die "File has zero size.\n";
	my	$blksize  = int ($filesize / 10);
	
	while (1) {
		$num_read = sysread(SRC, $buffer, $blksize);
		last if ($num_read == 0); 										
		die ("Error reading from file [$src]: $!\n") if (!defined($num_read));	
		
		my $offset = 0;
		while ($num_read){
			$num_wrote = syswrite(DST,$buffer,$num_read,$offset);
			die ("Error writing to file [$dst]: $!\n") if (!defined($num_wrote));
			$num_read -= $num_wrote;
			$offset	+= $num_wrote;
		}
		
		$perc_done += 10 unless $perc_done == 100;
		&$callback($perc_done) or die ("Copy canceled.\n");		
	}	
}

sub FileProgress () {
	my $percent = shift;
	print "$percent% done\n";	
	return 1;
}

if (@ARGV == 2) {
	my	$source		= shift @ARGV;
	my	$destination 	= shift @ARGV;
	&CopyFileProgress($source,$destination,\&FileProgress);
}else{
	print "\n\nUSAGE: copy.pl <source filename> <destination filename>\n\n";
}