Sorry if this sounds like a beginner question but after reading through a lot of material I have some questions.
Firstly, if a contract has already been created can I call its functions if I know its ABI & address? I think
contract(ABI).at(contractAddress) does this but I found the description rather ambiguous.
Secondly, if I am running web3 by direct library import without MetaMask or Mist when I initiate a function call who is the
msg.sender? If MetaMask or Mist are running is the
msg.sender the currently signed in wallet?
Finally, if I want to create a browser Dapp, how do I ensure some functions can only be invoked by the Dapp and no one else (Not even the owner)?
Thanks in advance!