'walletpassphrase' RPC command should extend unlock time if already unlocked #1528

If I run:

bitcoind walletpassphrase $password 60

and make a payment, then 58 seconds later run it again to make another payment, I get an error message:

error: {"code":-17,"message":"Error: Wallet is already unlocked."}

then, a couple of seconds later, when I go to make the 2nd payment, the first unlock has timed out, causing the payment to fail.

Better would be if the 2nd call to walletpassphrase just reset the timeout, either to the specified new timeout, or to max(old-expire-time, new-expire-time).

As it is, all I know is that the wallet is currently unlocked, but may well be locked again by the time I get to use it.

Also posted this issue earlier - #1527

Sounds like a good idea, agreed. The current behavior is unreliable, if it is impossible to guarantee an unlocked wallet during a command.

Closing as a dup of #1527.

D:\比特币\bitcoin-0.8.3-win32\bitcoin-0.8.3-win32\daemon>bitcoind walletpassphra se bitcoin 3

D:\比特币\bitcoin-0.8.3-win32\bitcoin-0.8.3-win32\daemon>bitcoind sendfrom dazi0 03 177CFtLHwUq2xWUkG4MLxp5sqXU9S6yERB 0.00009 error: {"code":-13,"message":"Error: Please enter the wallet passphrase with wal letpassphrase first."}