This hook is called when a sign text is about to be updated, either as a result of player's manipulation or any other event, such as a plugin setting the sign text. Plugins may modify the text or refuse the update altogether.

See also the HOOK_UPDATED_SIGN hook for a similar hook called after the update.

Callback function

The default name for the callback function is OnUpdatingSign. It has the following signature:

function OnUpdatingSign(World, BlockX, BlockY, BlockZ, Line1, Line2, Line3, Line4, Player)

Parameters:

The function may return up to five values. If the function returns true as the first value, no other callbacks are called for this event and the sign is not updated. If the function returns no value or false as its first value, other plugins' callbacks are called.

The other up to four values returned are used to update the sign text, line by line, respectively. Note that other plugins may again update the texts (if the first value returned is false).

Code examples

Registering the callback

cPluginManager:AddHook(cPluginManager.HOOK_UPDATING_SIGN, MyOnUpdatingSign);

Add player signature

The following example appends a player signature to the last line, if the sign is updated by a player:

function OnUpdatingSign(World, BlockX, BlockY, BlockZ, Line1, Line2, Line3, Line4, Player)
	if (Player == nil) then
		-- Not changed by a player
		return false;
	end

	-- Sign with playername, allow other plugins to interfere:
	return false, Line1, Line2, Line3, Line4 .. Player:GetName();
end