binmode $fh;
read($fh, my $buf, 20000);

##</code><code>##

binmode $fh;
local $/ = \20000;
my $buf = <$fh>;

##</code><code>##

binmode $fh;
my $file = '';
1 while read($fh, $file, 8*1024, length($file));

##</code><code>##

binmode $fh;
local $/;
my $file = <$fh>;