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ArbSys

ArbSys#

Precompiled contract that exists in every Arbitrum chain at address(100), 0x0000000000000000000000000000000000000064. Exposes a variety of system-level functionality. ArbSys provides systems functionality useful to some Arbitrum contracts. Any contract running on an Arbitrum Chain can call the chain's ArbSys.

Functions#

arbOSVersion() → uint256 (external)

Get internal version number identifying an ArbOS build

arbChainID() → uint256 (external)
arbBlockNumber() → uint256 (external)

Get Arbitrum block number (distinct from L1 block number; Arbitrum genesis block has block number 0)

withdrawEth(address destination) → uint256 (external)

Send given amount of Eth to dest from sender. This is a convenience function, which is equivalent to calling sendTxToL1 with empty calldataForL1.

Parameters:#

  • destination: recipient address on L1
sendTxToL1(address destination, bytes calldataForL1) → uint256 (external)

Send a transaction to L1

Parameters:#

  • destination: recipient address on L1
  • calldataForL1: (optional) calldata for L1 contract call
getTransactionCount(address account) → uint256 (external)

get the number of transactions issued by the given external account or the account sequence number of the given contract

Parameters:#

  • account: target account
getStorageAt(address account, uint256 index) → uint256 (external)

get the value of target L2 storage slot This function is only callable from address 0 to prevent contracts from being able to call it

Parameters:#

  • account: target account
  • index: target index of storage slot
isTopLevelCall() → bool (external)

check if current call is coming from l1

Events#

EthWithdrawal(address destAddr, uint256 amount)
L2ToL1Transaction(address caller, address destination, uint256 uniqueId, uint256 batchNumber, uint256 indexInBatch, uint256 arbBlockNum, uint256 ethBlockNum, uint256 timestamp, uint256 callvalue, bytes data)