Is there a 'command' to get the max supply of bitcoin that will ever exist using the bitcoin-cli? I would like to know if there a way('command') to know what is the max supply of bitcoin using my own node without trusting a third party. 

Also if anyone could explain to me why :


  bitcoin-cli gettxoutsetinfo


returns this message when written: 

*error: Could not connect to the server 127.0.0.1:8332 (error code 0 - "timeout reached")
    Make sure the bitcoind server is running and that you are connecting to the correct RPC port.*


Is that bcuz I'm running behind tor? Would be great if some of you guys can expand on these 2 doubts.
In a sense, such a command would be trusting a third party: any putative answer would be that given by whoever supplied that code to you; and it may not be trustworthy - it could tell you it was 21 million, but behind the scenes actually use, say, 42 million.  

The nearest you could do would be to download the source code from a proper source and, having verified your download, check the file src/amount.h for the line static const CAmount MAX_MONEY = 21000000 * COIN; before building the software yourself. You are now more sure that your node has the proper max supply.