Difference between revisions of "OP RETURN"

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===OP_RETURN Functionality===
 
===OP_RETURN Functionality===
OP_RETURN terminates the script leaving the stack as-is and letting the result on top of the stack determine the success or failure of the script. OP_RETURN can be used in combination with [[Opcodes_used_in_Bitcoin_Script#Flow_control|flow control]] opcodes to implement branching, conditional logic in scripts.
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OP_RETURN terminates the script leaving the stack as-is and letting the result on top of the stack determine the success or failure of the script. Note that if the top stack is non-empty and non-zero (zero including a string of zeros, of zero bytes), then it is considered as successful. Otherwise, it is considered as fail. OP_RETURN can be used in combination with [[Opcodes_used_in_Bitcoin_Script#Flow_control|flow control]] opcodes to implement branching, conditional logic in scripts.
  
 
===Example===  
 
===Example===  

Revision as of 10:50, 7 February 2020

OP_RETURN is a script opcode used to terminate the script and return the top value on the stack. This opcode is analogous to the return function in programming languages. The OP_RETURN opcode has a controversial history in Bitcoin and as a result has been primarily used as a means of storing data on the blockchain.

OP_RETURN Functionality

OP_RETURN terminates the script leaving the stack as-is and letting the result on top of the stack determine the success or failure of the script. Note that if the top stack is non-empty and non-zero (zero including a string of zeros, of zero bytes), then it is considered as successful. Otherwise, it is considered as fail. OP_RETURN can be used in combination with flow control opcodes to implement branching, conditional logic in scripts.

Example

The below script is a metanet node that attaches the Metanet data to a UTXO with funds. This can be used to ensure that metanet nodes are left in the UTXO set

𝑇𝑥𝐼𝐷𝑛𝑜𝑑𝑒
Inputs Outputs
<sigmetaParent> <pubKeymetaParent> <sigscript> <pubKeyscript> DUP HASH160 <pkhscript> EQUALVERIFY CHECKSIG RETURN <meta> <pkmetaNode> <txidmetaParent>