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@ -25,8 +25,7 @@ used.
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[role="pagebreak-before less_space_h1"]
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=== Transaction Scripts and Script Language
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((("scripting", "transactions and",
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id="Stransact06")))The original version of Bitcoin introduced a new
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((("scripting", "transactions and",id="Stransact06")))The original version of Bitcoin introduced a new
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programming language called _Script_, a Forth-like stack-based
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language. Both the script placed in an output and the legacy
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input script used in a spending transaction are written in this scripting
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@ -312,8 +311,7 @@ image::images/mbc2_0606.png["Tx_Script_P2PubKeyHash_2"]
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[[multisig]]
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=== Scripted multisignatures
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((("scripting",
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"multisignature scripts", id="Smulti07")))((("multisignature
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((("scripting","multisignature scripts", id="Smulti07")))((("multisignature
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scripts")))Multisignature scripts set a condition where _k_ public keys
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are recorded in the script and at least _t_ of those must provide
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signatures to spend the funds, called t-of-k.
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@ -475,8 +473,7 @@ introduced in 2012 as a powerful new type of operation that greatly
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simplifies the use of complex scripts. To explain the need
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for P2SH, let's look at a practical example.
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((("Pay-to-Script-Hash
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(P2SH)", "import/export example")))
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((("Pay-to-Script-Hash(P2SH)", "import/export example")))
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Mohammed is an electronics importer based in Dubai. Mohammed's
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company uses Bitcoin's multisignature feature extensively for its
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corporate accounts. Multisignature scripts are one of the most common
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@ -609,8 +606,7 @@ If the redeem script hash matches, the redeem script is executed:
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==== P2SH Addresses
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((("bitcoin
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improvement proposals", "Address Format for P2SH (BIP13)")))Another
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((("bitcoinimprovement proposals", "Address Format for P2SH (BIP13)")))Another
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important part of the P2SH feature is the ability to encode a script
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hash as an address, as defined in BIP13. P2SH addresses are Base58Check
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encodings of the 20-byte hash of a script, just like Bitcoin addresses
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@ -680,8 +676,7 @@ spent.
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[[op_return]]
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=== Data Recording Output (OP_RETURN)
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((("data recording
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(nonpayment data)")))((("blockchain (the)",
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((("data recording(nonpayment data)")))((("blockchain (the)",
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"nonpayment data recording")))Bitcoin's
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distributed and timestamped blockchain has potential uses
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beyond payments. Many developers have tried to use the transaction
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@ -771,8 +766,7 @@ It is important to understand the limitations of transaction lock time. The only
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==== Check Lock Time Verify (OP_CLTV)
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((("scripting", "timelocks", "Check Lock Time
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Verify (OP_CLTV)")))((("bitcoin improvement proposals",
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((("scripting", "timelocks", "Check Lock TimeVerify (OP_CLTV)")))((("bitcoin improvement proposals",
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"OP_CHECKLOCKTIMEVERIFY (BIP65)")))In December 2015, a new form of
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timelock was introduced to Bitcoin as a soft fork upgrade. Based on a
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specification in BIP65, a new script operator called
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@ -887,8 +881,7 @@ https://github.com/bitcoin/bips/blob/master/bip-0065.mediawiki[BIP65
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[[op_csv]]
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==== Relative Timelocks
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Lock time and +OP_CLTV+ are ((("scripting", "timelocks", "relative
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timelocks")))both
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Lock time and +OP_CLTV+ are ((("scripting", "timelocks", "relativetimelocks")))both
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_absolute timelocks_ in that they specify an absolute point in time. The
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next two timelock features we will examine are _relative timelocks_ in
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that they specify, as a condition of spending an output, an elapsed time
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@ -909,8 +902,7 @@ on the value of +sequence+, a transaction field that is set in every
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transaction input. Script-level relative timelocks are implemented with
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the +OP_CHECKSEQUENCEVERIFY+ (OP_CSV) opcode.
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((("bitcoin improvement
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proposals", "CHECKSEQUENCEVERIFY (BIP112)")))Relative timelocks are
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((("bitcoin improvementproposals", "CHECKSEQUENCEVERIFY (BIP112)")))Relative timelocks are
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implemented according to the specifications in
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https://github.com/bitcoin/bips/blob/master/bip-0068.mediawiki[BIP68,
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Relative lock-time using consensus-enforced sequence numbers] and
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@ -961,8 +953,7 @@ CHECKSEQUENCEVERIFY].
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=== Scripts with Flow Control (Conditional Clauses)
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((("conditional clauses",
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id="condition07")))One of the more
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((("conditional clauses",id="condition07")))One of the more
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powerful features of Bitcoin Script is flow control, also known as
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conditional clauses. You are probably familiar with flow control in
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various programming languages that use the construct +IF...THEN...ELSE+.
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theresa jones
8 months ago