#!/usr/bin/perl
#generally use File::Compare available in Perl5.8

print cmp_file(@ARGV) ? "equal\n" : "not equal\n";

#################

use constant BUF_SIZE => 4096;

sub cmp_file {
    my ( $f1, $f2 ) = @_;
    open my $h1, $f1 or die "gah $f1: $!";
    open my $h2, $f2 or die "gah $f2: $!";
    binmode $h1;
    binmode $h2;
    my ( $buf1, $buf2 );
    my $equal = 0;
    while ( read $h1, $buf1, BUF_SIZE ) {
        read $h2, $buf2, BUF_SIZE;
        last unless $equal = ( $buf1 eq $buf2 );
    }
    return $equal and eof $h2;
}
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