Lo, The code below gives different results if the binmode statement is removed. All the code does is print the md5sum of a file using Digest::MD5. When I remove the CR from the output file, the md5 agrees with the md5 of the filehandle in the script. So, it looks like the md5 using the filehandle is somehow getting the file without the crlf layer. So, any ideas? I have a workaround, but it has piqued my curiousity... The general logic is 1) Open file, autoflush 2) binmode crlf 3) write "Hello world\n" 4) seek 0,0. 5) Get md5 using filehandle 6) get md5 by opening file 
#! /usr/bin/perl -w
use strict;
use diagnostics;

use File::Temp();
use File::Copy;

my $FH = File::Temp->new ( TEMPLATE => 'tmpXXXXXXXXXX',
                           SUFFIX   => '.xml_out',
                           DIR      => '/tmp',
                           UNLINK   => 1
                         );

$FH->autoflush(1);

binmode( $FH, ':crlf' );

print $FH "Hello World\n";

my $tgt_file = '/tmp/JD';
copy ( $FH->filename, $tgt_file );

require Digest::MD5;
my $md5;
$FH->seek(0,0);
$md5 = Digest::MD5->new->addfile( $FH );
print 'by FH: ',$md5->hexdigest,"\n";


my $md52;
open(FILE, $tgt_file) or die "Can't open : $!";
binmode(FILE);
$md52 = Digest::MD5->new->addfile(*FILE);
close FILE;
print 'by FILE1: ',$md52->hexdigest,"\n";


my $md53;
open(FILE, $FH->filename) or die "Can't open : $!";
binmode(FILE);
$md53 = Digest::MD5->new->addfile(*FILE);
close FILE;
print 'by FILE2: ',$md53->hexdigest,"\n";

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In reply to binmode layer and seek by ftumsh

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