As stated in the title I've been looking at the Batch Overflow issue that happened last year where someone printed tokens out of nowhere.
I see that when you create a token, you specify a totalSupply of the token that you are going to create so the amount of tokens must not be bigger than the TotalSupply.
When the BatchOverflow problem occured last year, someone printed tokens out of nowhere, that leads to the question which I cannot solve.
How was it possible for the guy that discovered the bug to create more tokens than the totalSupply specified ?
Isn't the totalSupply a constant value in the erc20 contract ?