We should learn about new peers via address messages.
An inbound peer connecting to us tells us nothing about
its ability to accept incoming connections from us, so
we shouldn't assume that we can connect to it based on
this.
The vast majority of nodes on the network do not accept
incoming connections, adding them will only slow down
the process of making a successful connection in the
future.
Nodes which have configured themselves to not announce would prefer we
not violate their privacy by announcing them in GETADDR responses.
Tests if addresses are online or offline by briefly connecting to them. These short lived connections are referred to as feeler connections. Feeler connections are designed to increase the number of fresh online addresses in tried by selecting and connecting to addresses in new. One feeler connection is attempted on average once every two minutes.
This change was suggested as Countermeasure 4 in
Eclipse Attacks on Bitcoin’s Peer-to-Peer Network, Ethan Heilman,
Alison Kendler, Aviv Zohar, Sharon Goldberg. ePrint Archive Report
2015/263. March 2015.
Commands can be executed with bracket syntax, example: `getwalletinfo()`.
Commands can be nested, example: `sendtoaddress(getnewaddress(), 10)`.
Simple queries are possible: `listunspent()[0][txid]`
Object values are accessed with a non-quoted string, example: [txid].
Fully backward compatible.
`generate 101` is identical to `generate(101)`
Result value queries indicated with `[]` require the new brackets syntax.
Comma as argument separator is now also possible: `sendtoaddress,<address>,<amount>`
Space as argument separator works also with the bracket syntax, example: `sendtoaddress(getnewaddress() 10)
No dept limitation, complex commands are possible:
`decoderawtransaction(getrawtransaction(getblock(getbestblockhash())[tx][0]))[vout][0][value]`
Remove the unused variable "blockTmp" in CMerkleTx::SetMerkleBranch. It
was previously used to read the block from disk if not provided as
argument, but is no longer needed.
The `pickDataDirectory()` function was calling `exit(0)` to quit
the application when the user closes the dialog without choosing
a data directory.
This is a bad idea because a background thread is created (to
check free space on the drive of the currently selected datadir).
The thread is not stopped and unwound properly, resulting in a potential
race condition somewhere deep in Qt.
So replace the `exit()` by a boolean return value, and let the
stack unwind normally.
Suhas Daftuar