settxfee amount
Set the transaction fee per kB for this wallet. Overrides the global -paytxfee command line parameter.
Arguments:
1. amount (numeric or string, required) The transaction fee in " + CURRENCY_UNIT + "/kB
Result
true|false (boolean) Returns true if successful
Examples:
> bitcoin-cli settxfee 0.00001
> curl --user myusername --data-binary '{"jsonrpc": "1.0", "id":"curltest", "method": "settxfee", "params": [0.00001] }' -H 'content-type: text/plain;' http://127.0.0.1:8332/