Bitcoin Forum

Bitcoin => Bitcoin Technical Support => Topic started by: Dr Bloggood on November 02, 2017, 05:51:25 PM



Title: How can I send a message with a transaction?
Post by: Dr Bloggood on November 02, 2017, 05:51:25 PM
A message e.g. like the one Satoshi sent with the Genesis block: "Chancellor on brink of second bailout for banks."

Just curious how to do this as a normal user.


Title: Re: How can I send a message with a transaction?
Post by: achow101 on November 02, 2017, 06:04:08 PM
The message that Satoshi included in the Genesis block is actually part of the Coinbase transaction of that block. Specifically, in the input of any Coinbase transaction, you can include whatever data that you want. Satoshi chose to put a string there. So if you want to do the same thing, then you must be a miner and set whatever you want in that part of the coinbase transaction of your blocks.

There are other ways to embed data in transactions. You can use an OP_RETURN output which allows you to make a provably unspendable output that has arbitrary data in it.


Title: Re: How can I send a message with a transaction?
Post by: DannyHamilton on November 02, 2017, 06:11:40 PM
Bitcoin is not a messaging system.

However, the OP_RETURN code was added so that some data could be embedded in the transaction outputs if someone wants to.

None of the standard wallets provide a user interface for embedding data, nor do they provide any method for viewing any embedded data.  This is because Bitcoin is not a messaging system.

However, there are services that will charge you a fee and will create transactions with embedded data for you.  Most of those services will also display that data on their website.


Title: Re: How can I send a message with a transaction?
Post by: Dr Bloggood on November 02, 2017, 06:21:51 PM
The message that Satoshi included in the Genesis block is actually part of the Coinbase transaction of that block. Specifically, in the input of any Coinbase transaction, you can include whatever data that you want. Satoshi chose to put a string there. So if you want to do the same thing, then you must be a miner and set whatever you want in that part of the coinbase transaction of your blocks.

There are other ways to embed data in transactions. You can use an OP_RETURN output which allows you to make a provably unspendable output that has arbitrary data in it.

Thank you! Only possible for miners, I see.

Would you mind explaining how I can use an OP_RETURN output? Do I have to run my own node in order to do that? Non-technical person here...


Title: Re: How can I send a message with a transaction?
Post by: Dr Bloggood on November 02, 2017, 06:26:04 PM
Bitcoin is not a messaging system.

However, the OP_RETURN code was added so that some data could be embedded in the transaction outputs if someone wants to.

None of the standard wallets provide a user interface for embedding data, nor do they provide any method for viewing any embedded data.  This is because Bitcoin is not a messaging system.

However, there are services that will charge you a fee and will create transactions with embedded data for you.  Most of those services will also display that data on their website.

Yes, I get that Bitcoin is not a messaging system. I was asking out of curiosity, and also to maybe in the future mark certain addresses as proof for tax reasons. It's not good to spam and congest the network, I know.

Which services would do that, can you name some?

And btw, I applaud you for restlessly answer questions on this forum and educating people. Bitcoin needs people like you, so thanks!


Title: Re: How can I send a message with a transaction?
Post by: cryptoDARO on November 02, 2017, 06:31:22 PM
You can't do it with Bitcoin but there are Ethereum apps which allow you exactly what you described. I think you can do it with Status (SNT) and several more apps.
Check out Byteball too.


Title: Re: How can I send a message with a transaction?
Post by: Dr Bloggood on November 02, 2017, 06:37:05 PM
You can't do it with Bitcoin but there are Ethereum apps which allow you exactly what you described. I think you can do it with Status (SNT) and several more apps.
Check out Byteball too.

Thanks, looking for a way to do it with BTC though. I'm not gonna choose my crypto after its ability to send a message with a transaction. ;)