Running Bitcoin

There are two variations of the official bitcoin program available; one with a graphical user interface (usually referred to as just “Bitcoin”), and a 'headless' version (called bitcoind). They are completely compatible with each other, and take the same command-line arguments, read the same configuration file, and read and write the same data files. You can run one copy of either Bitcoin or bitcoind on your system at a time (if you accidently try to launch another, the copy will let you know that Bitcoin or bitcoind is already running and will exit).

Command-line arguments

Give Bitcoin (or bitcoind) the -? or –help argument and it will print out a list of the most commonly used command-line arguments and then exit:

Usage:

 bitcoin [options]                     
 bitcoin [options] <command> [params]  Send command to -server or bitcoind
 bitcoin [options] help                List commands
 bitcoin [options] help <command>      Get help for a command

Options:

 -conf=<file>      Specify configuration file (default: bitcoin.conf)
 -gen              Generate coins
 -gen=0            Don't generate coins
 -min              Start minimized
 -datadir=<dir>    Specify data directory
 -proxy=<ip:port>  Connect through socks4 proxy
 -addnode=<ip>     Add a node to connect to
 -connect=<ip>     Connect only to the specified node
 -server           Accept command line and JSON-RPC commands
 -daemon           Run in the background as a daemon and accept commands
 -?                This help message

Bitcoin.conf Configuration File

All command-line options (except for -datadir and -conf) may be specified in a configuration file, and all configuration file options may also be specified on the command line. Command-line options override values set in the configuration file.

The configuration file is a list of setting=value pairs, one per line, with optional comments starting with the '#' character.

The configuration file is not automatically created; you can create it using your favorite plain-text editor. By default, Bitcoin (or bitcoind) will look for a file named 'bitcoin.conf' in the bitcoin data directory, but both the data directory and the configuration file path may be changed using the -datadir and -conf command-line arguments.

Operating System	Default bitcoin datadir	Typical path to configuration file
Windows	%APPDATA%\Bitcoin\	:\Documents and Settings\username\Application Data\Bitcoin\bitcoin.conf
Linux	$HOME/.bitcoin/	/Users/username/.bitcoin/bitcoin.conf
Mac OSX	$HOME/Library/Application Support/Bitcoin/	/Users/username/Library/Application Support/Bitcoin/bitcoin.conf

Sample Bitcoin.conf

Here is a sample bitcoin.conf file, containing every option set to its default value.

 # bitcoin.conf configuration file. Lines beginning with # are comments.

 # Network-related settings:

 # Run on the test network instead of the real bitcoin network.
 #testnet=1

 # Connect via a socks4 proxy
 #proxy=127.0.0.1:9050

 # Use as many addnode= settings as you like to connect to specific peers
 #addnode=69.164.218.197
 #addnode=10.0.0.2:8333

 # ... or use as many connect= settings as you like to connect ONLY
 # to specific peers:
 #connect=69.164.218.197
 #connect=10.0.0.1:8333

 # Do not use Internet Relay Chat (irc.lfnet.org #bitcoin channel) to
 # find other peers.
 #noirc=1

 # Maximum number of inbound+outbound connections.
 #maxconnections=

 # JSON-RPC options (for controlling a running Bitcoin/bitcoind process)

 # server=1 tells Bitcoin to accept JSON-RPC commands.
 #server=1

 # You must set rpcuser and rpcpassword to secure the JSON-RPC api
 #rpcuser=Ulysseys
 #rpcpassword=YourSuperGreatPasswordNumber_385593

 # How many seconds bitcoin will wait for a complete RPC HTTP request.
 # after the HTTP connection is established. 
 rpctimeout=30

 # By default, only RPC connections from localhost are allowed.  Specify
 # as many rpcallowip= settings as you like to allow connections from
 # other hosts (and you may use * as a wildcard character):
 #rpcallowip=10.1.1.34
 #rpcallowip=192.168.1.*

 # Listen for RPC connections on this TCP port:
 rpcport=8332

 # You can use Bitcoin or bitcoind to send commands to Bitcoin/bitcoind
 # running on another host using this option:
 rpcconnect=127.0.0.1

 # Use Secure Sockets Layer (also known as TLS or HTTPS) to communicate
 # with Bitcoin -server or bitcoind
 #rpcssl=1

 # OpenSSL settings used when rpcssl=1
 rpcsslciphers=TLSv1+HIGH:!SSLv2:!aNULL:!eNULL:!AH:!3DES:@STRENGTH
 rpcsslcertificatechainfile=server.cert
 rpcsslprivatekeyfile=server.pem

 # Miscellaneous options

 # Set gen=1 to attempt to generate bitcoins
 gen=0

 # Use SSE instructions to try to generate bitcoins faster.
 #4way=1

 # Pre-generate this many public/private key pairs, so wallet backups will be valid for
 # both prior transactions and several dozen future transactions.
 keypool=100

 # Pay an optional transaction fee every time you send bitcoins.  Transactions with fees
 # are more likely than free transactions to be included in generated blocks, so may
 # be validated sooner.
 paytxfee=0.00

 # Allow direct connections for the 'pay via IP address' feature.
 #allowreceivebyip=1

 # User interface options

 # Start Bitcoin minimized
 #min=1

 # Minimize to the system tray
 #minimizetotray=1