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Built-In Functions

Introduction​

MultiversX protocol has a set of built-in functions. A built-in function is a special protocol-side function that doesn't require a specific smart contract address as receiver of the transaction. When such a function is called via a transaction, built-in handlers are triggered and will execute it.

Calls to these functions are considered built-in function calls and are treated different than other smart contract calls.

This documentation is subject to change, but at the time of writing, the current built-in functions were:

  • ClaimDeveloperRewards
  • ChangeOwnerAddress
  • SetUserName
  • SaveKeyValue
  • ESDTTransfer
  • ESDTBurn
  • ESDTFreeze
  • ESDTUnFreeze
  • ESDTWipe
  • ESDTPause
  • ESDTUnPause
  • ESDTSetRole
  • ESDTUnSetRole
  • ESDTSetLimitedTransfer
  • ESDTUnSetLimitedTransfer
  • ESDTLocalBurn
  • ESDTLocalMint
  • ESDTNFTTransfer
  • ESDTNFTCreate
  • ESDTNFTAddQuantity
  • ESDTNFTBurn
  • ESDTNFTAddURI
  • ESDTNFTUpdateAttributes
  • MultiESDTNFTTransfer

ClaimDeveloperRewards​

This function is to be used by Smart Contract owners in order to claim the fees accumulated during smart contract calls. Currently, the developer reward is set to 30% of the fee of each smart contract call.

ClaimDeveloperRewardsTransaction {
    Sender: <the owner of the SC>
    Receiver: <SC address>
    Value: 0
    GasLimit: 6_000_000
    Data: "ClaimDeveloperRewards"
}

For more details about how arguments have to be encoded, check here.

note

The amount of available developer rewards can be viewed via Get Address endpoint when using the smart contract as the bech32Address.

ChangeOwnerAddress​

ChangeOwnerAddress is the function to be called by a Smart Contract's owner when a new owner is desired.

ChangeOwnerAddressTransaction {
    Sender: <the current owner of the SC>
    Receiver: <SC address>
    Value: 0
    GasLimit: 6_000_000
    Data: "ChangeOwnerAddress" +
          "@" + <new owner address in hexadecimal encoding>
}

For more details about how arguments have to be encoded, check here.

SetUserName​

SetUserName is used to set an username for a given address. The receiver's address has to be the DNS smart contract address of the address.

SetUserNameTransaction {
    Sender: <sender>
    Receiver: <DNS address that corresponds to the sender>
    Value: 0
    GasLimit: 1_200_000
    Data: "SetUserName@" +
          "@" + <username in hexadecimal encoding>
}

For more details about how arguments have to be encoded, check here.

SaveKeyValue​

SaveKeyValue is used to store a given key-value under an address's storage. More details and the transaction's format are already covered here.

ESDT and NFT built-in functions​

Most of the ESDT and NFT related built-in function are already described in the ESDT and NFT sections.