_owner
._value
amount of tokens to address _to
, and MUST fire the Transfer event. The function SHOULD throw if the message callerβs account balance does not have enough tokens to spend._value
amount of tokens from address _from
to address _to
, and MUST fire the Transfer event._from
account has deliberately authorized the sender of the message via some mechanism._spender
to withdraw from your account multiple times, up to the _value
amount. If this function is called again it overwrites the current allowance with _value
._spender
is still allowed to withdraw from _owner
._spender
is still allowed to withdraw from you._spender
is still allowed to withdraw from you._from
address set to 0x0 when tokens are created.approve(address _spender, uint256 _value)
, increaseAllowance(address _spender, uint256 _delta)
or decreaseAllowance(address _spender, uint256 _delta)
. OPTIONAL may trigger on any successful call to transferFrom(address _from, address _to, uint256 _value)
which changes allowance, but it is not required.