local h1, h2, h3 = debug.gethook() 
debug.sethook() 

local gsub = string.gsub
local char = string.char
local byte = string.byte
local bitXor = bitXor

local function encodeCaesarXor(str, key) 
	return (gsub(str, '.', function(s) 
		return char(((bitXor(s:byte(s), 5) + key) % 256)) 
	end)) 
end 

local function decodeCaesarXor(str, key) 
	return (gsub(str, '.', function(s) 
		return char(((bitXor(byte(s)-key, 5)) % 256)) 
	end)) 
end

local function caesar(str, key) 
	return (gsub(str, '.', function(s) 
		return char((byte(s) + key) % 256)
	end)) 
end 

local file = fileOpen('1.dff')
	local buffer = fileRead(file, file.size)
fileClose(file)

local t=getTickCount()
buffer = caesar(buffer, 1)
print('ms: '..(getTickCount()-t))

local file = fileCreate('3.dff')
	local buffer = fileWrite(file, buffer)
fileClose(file)

debug.sethook (_, h1, h2, h3)