# reading (for example, a gif)
local $/ = undef;
open FILE, $file;
binmode(FILE); # needed for win32
$gif = <FILE>;
$hexgif = unpack ("H*", $gif); # convert gif to hex string

# printing
$gif = pack ("H*", $hexgif); # convert hex string back to binary data
print "Content-type: image/gif\n\n";
binmode(STDOUT);
print $gif;