#!/usr/bin/perl -w
# -*-Perl-*-

use strict;
use FileHandle;
use Digest::MD5;

my $sourceFile = $ARGV[0];
my $destFile   = $ARGV[1];
my $inFile     = new FileHandle;
my $outFile    = new FileHandle;
my $inMD5      = Digest::MD5->new;
my $outMD5     = Digest::MD5->new;
my ( 
    $fileLength,
    $fileBuffer,
    $fileOffset
   );

$inFile->open ( "<$sourceFile" )
  or die "Could not open $sourceFile:$!\n";
$inMD5->addfile ( $inFile );

$outFile->open ( ">$destFile" )
  or die "Could not open $destFile:$!\n";

print $inMD5->md5_base64 , "\n";

# borrowed from "Programming Perl"

my $blockSize = ( stat $inFile )[11] || 16384;
while ( $fileLength  = sysread $inFile, $fileBuffer, $blockSize ) {
    if ( !defined $fileLength ) {
 next
   if $! =~ /^Interrupted/;
 die "System read error: $!\n";
    }
    my $fileOffset = 0;
    while ( $fileLength ) {
 my $written = syswrite $outFile, $fileBuffer, $fileLength, $fileOffset;
 die "System write error: $!\n"
   unless defined $written;
 $fileLength -= $written;
 $fileOffset += $written;
    };
}

$outMD5->addfile ( $outFile );
print $outMD5->md5_base64 , "\n";

$inFile->close;
$outFile->close;