olddelete = fs.delete
oldterminate = os.pullEvent
os.pullEvent = os.pullEventRaw

function removefile(filename)
	if filename == "startup" then
		error("Access Denied")
	else
		olddelete(filename)
	end
end

fs.delete = removefile

local bExit = false
term.clear()
term.setCursorPos(1,1)
print(os.version().. " - Used PC")


-- Read commands and execute them
local tCommandHistory = {}
while not bExit do
	write( shell.dir() .. "> " )

	local sLine = read( nil, tCommandHistory )
	table.insert( tCommandHistory, sLine )

	local tWords = {}
	for match in string.gmatch(sLine, "[^ \t]+") do
		table.insert( tWords, match )
	end

	local sCommand = tWords[1]
	if sCommand then
		if sCommand == "edit" and tWords[2] == "startup" then
			print("Access Denied")
		else
			os.pullEvent = oldterminate
			shell.run( sCommand, unpack( tWords, 2 ) )
			os.pullEvent = os.pullEventRaw
		end
	end
end