@ -352,7 +352,7 @@ Eugenia's wallet application will calculate the appropriate fee by measuring the
[[tx_script]]
=== Transaction Scripts and Script Language
((("transactions", "scripts and script language", id="Tsript06")))The bitcoin transaction script language, called _Script_, is a Forth-like reverse-polish notation stack-based execution language. If that sounds like gibberish, you probably haven't studied 1960's programming languages, but that's ok—we will explain it all in this chapter. Both the locking script placed on a UTXO and the unlocking script are written in this scripting language. When a transaction is validated, the unlocking script in each input is executed alongside the corresponding locking script to see if it satisfies the spending condition.
((("transactions", "scripts and script language", id="Tsript06")))((("bitcoin", "scripting", id="BCscript06")))The bitcoin transaction script language, called _Script_, is a Forth-like reverse-polish notation stack-based execution language. If that sounds like gibberish, you probably haven't studied 1960's programming languages, but that's ok—we will explain it all in this chapter. Both the locking script placed on a UTXO and the unlocking script are written in this scripting language. When a transaction is validated, the unlocking script in each input is executed alongside the corresponding locking script to see if it satisfies the spending condition.
Script is a very simple language that was designed to be limited in scope and executable on a range of hardware, perhaps as simple as an embedded device. It requires minimal processing and cannot do many of the fancy things modern programming languages can do. For its use in validating programmable money, this is a deliberate security feature.
@ -483,7 +483,7 @@ The two scripts together would form the following combined validation script:
When executed, this combined script will evaluate to TRUE if, and only if, the unlocking script matches the conditions set by the locking script. In other words, the result will be TRUE if the unlocking script has a valid signature from the cafe's private key that corresponds to the public key hash set as an encumbrance.
Figures pass:[<a data-type="xref" href="#P2PubKHash1" data-xrefstyle="select: labelnumber">#P2PubKHash1</a>] and pass:[<a data-type="xref" href="#P2PubKHash2" data-xrefstyle="select: labelnumber">#P2PubKHash2</a>] show (in two parts) a step-by-step execution of the combined script, which will prove this is a valid transaction.((("", startref="Tsript06")))
Figures pass:[<a data-type="xref" href="#P2PubKHash1" data-xrefstyle="select: labelnumber">#P2PubKHash1</a>] and pass:[<a data-type="xref" href="#P2PubKHash2" data-xrefstyle="select: labelnumber">#P2PubKHash2</a>] show (in two parts) a step-by-step execution of the combined script, which will prove this is a valid transaction.((("", startref="Tsript06")))((("", startref="BCscript06")))
[[P2PubKHash1]]
.Evaluating a script for a P2PKH transaction (part 1 of 2)
judymcconville@roadrunner.com
7 years ago