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				package File::Compare;								use 5.005_64;				use strict;				our($VERSION, @ISA, @EXPORT, @EXPORT_OK, $Too_Big);								require Exporter;				use Carp;								$VERSION = '1.1002';				@ISA = qw(Exporter);				@EXPORT = qw(compare);				@EXPORT_OK = qw(cmp compare_text);								$Too_Big = 1024 * 1024 * 2;								sub VERSION {				    # Version of File::Compare				    return $File::Compare::VERSION;				}								sub compare {				    croak("Usage: compare( file1, file2 [, buffersize]) ")				      unless(@_ == 2 || @_ == 3);								    my ($from,$to,$size) = @_;				    my $text_mode = defined($size) && (ref($size) eq 'CODE' || $size < 0);								    my ($fromsize,$closefrom,$closeto);				    local (*FROM, *TO);								    croak("from undefined") unless (defined $from);				    croak("to undefined") unless (defined $to);								    if (ref($from) && 				        (UNIVERSAL::isa($from,'GLOB') || UNIVERSAL::isa($from,'IO::Handle'))) {					*FROM = *$from;				    } elsif (ref(\$from) eq 'GLOB') {					*FROM = $from;				    } else {					open(FROM,"					unless ($text_mode) {					    binmode FROM;					    $fromsize = -s FROM;					}					$closefrom = 1;				    }								    if (ref($to) &&				        (UNIVERSAL::isa($to,'GLOB') || UNIVERSAL::isa($to,'IO::Handle'))) {					*TO = *$to;				    } elsif (ref(\$to) eq 'GLOB') {					*TO = $to;				    } else {					open(TO,"					binmode TO unless $text_mode;					$closeto = 1;				    }								    if (!$text_mode && $closefrom && $closeto) {					# If both are opened files we know they differ if their size differ					goto fail_inner if $fromsize != -s TO;				    }								    if ($text_mode) {					local $/ = "\n";					my ($fline,$tline);					while (defined($fline = )) {					    goto fail_inner unless defined($tline = );					    if (ref $size) {						# $size contains ref to comparison function						goto fail_inner if &$size($fline, $tline);					    } else {						goto fail_inner if $fline ne $tline;					    }					}					goto fail_inner if defined($tline = );				    }				    else {					unless (defined($size) && $size > 0) {					    $size = $fromsize || -s TO || 0;					    $size = 1024 if $size < 512;					    $size = $Too_Big if $size > $Too_Big;					}									my ($fr,$tr,$fbuf,$tbuf);					$fbuf = $tbuf = '';					while(defined($fr = read(FROM,$fbuf,$size)) && $fr > 0) {					    unless (defined($tr = read(TO,$tbuf,$fr)) && $tbuf eq $fbuf) {						goto fail_inner;					    }					}					goto fail_inner if defined($tr = read(TO,$tbuf,$size)) && $tr > 0;				    }								    close(TO) || goto fail_open2 if $closeto;				    close(FROM) || goto fail_open1 if $closefrom;								    return 0;				    				  # All of these contortions try to preserve error messages...				  fail_inner:				    close(TO) || goto fail_open2 if $closeto;				    close(FROM) || goto fail_open1 if $closefrom;								    return 1;								  fail_open2:				    if ($closefrom) {					my $status = $!;					$! = 0;					close FROM;					$! = $status unless $!;				    }				  fail_open1:				    return -1;				}								sub cmp;				*cmp = \&compare;								sub compare_text {				    my ($from,$to,$cmp) = @_;				    croak("Usage: compare_text( file1, file2 [, cmp-function])")					unless @_ == 2 || @_ == 3;				    croak("Third arg to compare_text() function must be a code reference")					if @_ == 3 && ref($cmp) ne 'CODE';								    # Using a negative buffer size puts compare into text_mode too				    $cmp = -1 unless defined $cmp;				    compare($from, $to, $cmp);				}								1;								__END__								=head1 NAME								File::Compare - Compare files or filehandles								=head1 SYNOPSIS								  	use File::Compare;									if (compare("file1","file2") == 0) {					    print "They're equal\n";					}								=head1 DESCRIPTION								The File::Compare::compare function compares the contents of two				sources, each of which can be a file or a file handle.  It is exported				from File::Compare by default.								File::Compare::cmp is a synonym for File::Compare::compare.  It is				exported from File::Compare only by request.								File::Compare::compare_text does a line by line comparison of the two				files. It stops as soon as a difference is detected. compare_text()				accepts an optional third argument: This must be a CODE reference to				a line comparison function, which returns 0 when both lines are considered				equal. For example:								    compare_text($file1, $file2)								is basically equivalent to								    compare_text($file1, $file2, sub {$_[0] ne $_[1]} )								=head1 RETURN								File::Compare::compare return 0 if the files are equal, 1 if the				files are unequal, or -1 if an error was encountered.								=head1 AUTHOR								File::Compare was written by Nick Ing-Simmons.				Its original documentation was written by Chip Salzenberg.								=cut											

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