rpcauth command line arg does not work when there is no config file #20057

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<!-- Describe the issue -->

Expected behavior

specifying the command line arg -rpcauth={user}:{salt}${hash} from the output of rpcauth.py should allow you to authenticate with the user and password even when there is not a config file

Actual behavior

rpc command returns error: Authorization failed: Incorrect rpcuser or rpcpassword

To reproduce

run bitcoind version 0.20.1 with the command line arg -rpcauth={user}:{salt}${hash} from the output of rpcauth.py without creating a bitcoin.conf file. Then try to connect to the rpc with the username and password.

System information

bitcoind version 0.20.1 for linux downloaded from the website OS: ubuntu

if you then add a config file with rpcauth={user}:{salt}${hash} it works

The comment here #12209 (comment) about the dollar sign being consumed by the shell was the problem for me. To fix this, I just added a '\' before the dollar sign in the rpcauth argument to bitcoind. I think this should ideally create a warning message if the rpcauth argument is not properly formatted.

That would most likely explain it, thanks.