Use the console.
seems no parameter to define fees option (bitUSD or bts )
>> help wallet_market_cover
Usage:
wallet_market_cover <from_account_name> <quantity> <quantity_symbol> <cover_id> Used to place a request to cover an existing short position
Used to place a request to cover an existing short position
Parameters:
from_account_name (account_name, required): the account that will provide funds for the ask
quantity (string, required): the quantity of asset you would like to cover
quantity_symbol (asset_symbol, required): the type of asset you are covering (ie: USD)
cover_id (order_id, required): the order ID you would like to cover
Returns:
transaction_record
aliases: cover