Checking if sombody has an addon

[holon]

Can anybody point me in the right direction?

I've already tried using,
[LUA]util.IsValidModel("models/props_gammarays/tiberium.mdl")[/LUA]
on the client. But it always returns false!

Anybody got any ideas?

[Averice]

[lua]function _R.Player:HasAddon(addon)
return file.Exists("addons/"..tostring(addon).."/info.txt", true)
end
[/lua]
print(player:HasAddon("addon_name"))

Clientside obviously.

[|FlapJack|]

if GetAddonInfo(addonname) then

[TheMagician]

Or when the person creates an adodn, look through the code for a varibla that only exists in that addon, and check for it :)