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I copied and modified smart contracts from TenX and EOS. Below is my code.

From the sale contract, I'm able to execute functions in the token contract, like the way TenX has, such as token.mint(recipient, tokens). I added token.balanceOf(holder) and token.totalSupply() and they work. However token.transfer(_to, _value) does not work because msg.sender in BasicToken is zero or blank. How do I get this to work? (I'm doing this so that I can access the Token functions in remix.ethereum.org)

TenX has token.transferOwnership(owner) in their finishMinting function:

/**
   * @dev Allows the owner to close sale. This will create the 
   * restricted tokens.
   * Then the ownership of the token contract is transfered 
   * to this owner.
   */      
function finishMinting() public onlyOwner {
   uint issuedTokenSupply = token.totalSupply();
   uint restrictedTokens = issuedTokenSupply.mul(49).div(51);
   token.mint(multisigVault, restrictedTokens);
   token.finishMinting();
   token.transferOwnership(owner);
   MainSaleClosed();
}

I incorporated this into my closeSale function. But, I don't see how it transfers or changes owner. When sale contract is created/submitted, it creates the token contract and sets the owner in the token contract to be the sale contract. Isn't token.transferOwnership(owner) setting the owner to be the same owner? When I execute closeSale, owner value does not change. Does anyone know the purpose of this or if it changes the owner?

My code: (If you come across any, I welcome any suggestions to improve my code or indications of potential bugs. Thanks!)

pragma solidity ^0.4.11;

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control 
 * functions, this simplifies the implementation of "user permissions". 
 */
contract Ownable {
  address public owner;

  /** 
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  function Ownable() {
    owner = msg.sender;
  }

  /**
   * @dev Throws if called by any account other than the owner. 
   */
  modifier onlyOwner() {
    require(msg.sender == owner);
    _;
  }

  /**
   * @dev Allows the current owner to transfer control of the contract to a newOwner.
   * @param newOwner The address to transfer ownership to. 
   */
  function transferOwnership(address newOwner) onlyOwner {
    require(newOwner != address(0));
    owner = newOwner;
  }
}

/**
 * @title Authorizable
 * @dev Allows to authorize access to certain function calls
 * 
 * ABI
 * [{"constant":true,"inputs":[{"name":"authorizerIndex","type":"uint256"}],"name":"getAuthorizer","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_addr","type":"address"}],"name":"addAuthorized","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_addr","type":"address"}],"name":"isAuthorized","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"inputs":[],"payable":false,"type":"constructor"}]
 */
contract Authorizable {

  address[] authorizers;
  mapping(address => uint256) authorizerIndex;

  /**
   * @dev Throws if called by any account tat is not authorized. 
   */
  modifier onlyAuthorized {
    require(isAuthorized(msg.sender));
    _;
  }

  /**
   * @dev Contructor that authorizes the msg.sender. 
   */
  function Authorizable() {
    authorizers.length = 2;
    authorizers[1] = msg.sender;
    authorizerIndex[msg.sender] = 1;
  }

  /**
   * @dev Function to get a specific authorizer
   * @param authIndex index of the authorizer to be retrieved.
   * @return The address of the authorizer.
   */
  function getAuthorizer(uint256 authIndex) external constant returns(address) {
    return address(authorizers[authIndex + 1]);
  }

  /**
   * @dev Function to check if an address is authorized
   * @param _addr the address to check if it is authorized.
   * @return boolean flag if address is authorized.
   */
  function isAuthorized(address _addr) constant returns(bool) {
    return authorizerIndex[_addr] > 0;
  }

  /**
   * @dev Function to add a new authorizer
   * @param _addr the address to add as a new authorizer.
   */
  function addAuthorized(address _addr) external onlyAuthorized {
    authorizerIndex[_addr] = authorizers.length;
    authorizers.length++;
    authorizers[authorizers.length - 1] = _addr;
  }
}

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {
  function mul(uint256 a, uint256 b) internal constant returns (uint256) {
    uint256 c = a * b;
    assert(a == 0 || c / a == b);
    return c;
  }

  function div(uint256 a, uint256 b) internal constant returns (uint256) {
    // assert(b > 0); // Solidity automatically throws when dividing by 0
    uint256 c = a / b;
    // assert(a == b * c + a % b); // There is no case in which this doesn't hold
    return c;
  }

  function sub(uint256 a, uint256 b) internal constant returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  function add(uint256 a, uint256 b) internal constant returns (uint256) {
    uint256 c = a + b;
    assert(c >= a);
    return c;
  }
}

/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20Basic {
  uint256 public totalSupply;
  function balanceOf(address who) constant returns (uint256);
  function transfer(address to, uint256 value) returns (bool);
  //event Transfer(address indexed from, address indexed to, uint256 value);
  event Transfer(address from, address to, uint256 value);
}

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20 is ERC20Basic {
  function allowance(address owner, address spender) constant returns (uint256);
  function transferFrom(address from, address to, uint256 value) returns (bool);
  function approve(address spender, uint256 value) returns (bool);
  event Approval(address indexed owner, address indexed spender, uint256 value);
}

/**
 * @title Basic token
 * @dev Basic version of StandardToken, with no allowances. 
 */
contract BasicToken is ERC20Basic {
  using SafeMath for uint;

  mapping(address => uint256) balances;

  /**
   * @dev Fix for the ERC20 short address attack.
   */
  modifier onlyPayloadSize(uint256 size) {
     require(msg.data.length >= size + 4);
     _;
  }

  /**
  * @dev transfer token for a specified address
  * @param _to The address to transfer to.
  * @param _value The amount to be transferred.
  */
  function transfer(address _to, uint256 _value) onlyPayloadSize(2 * 32) returns (bool) {
    //balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    Transfer(msg.sender, _to, _value);
    return true;
  }

  /**
  * @dev Gets the balance of the specified address.
  * @param _owner The address to query the the balance of. 
  * @return An uint256 representing the amount owned by the passed address.
  */
  function balanceOf(address _owner) constant returns (uint256 balance) {
    return balances[_owner];
  }
}

/**
 * @title Standard ERC20 token
 *
 * @dev Implemantation of the basic standart token.
 * @dev https://github.com/ethereum/EIPs/issues/20
 * @dev Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 */
contract StandardToken is BasicToken, ERC20 {

  mapping (address => mapping (address => uint256)) allowed;

  /**
   * @dev Transfer tokens from one address to another
   * @param _from address The address which you want to send tokens from
   * @param _to address The address which you want to transfer to
   * @param _value uint the amout of tokens to be transfered
   */
  function transferFrom(address _from, address _to, uint256 _value) onlyPayloadSize(3 * 32) returns (bool) {
    var _allowance = allowed[_from][msg.sender];

    // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
    // if (_value > _allowance) throw;

    balances[_to] = balances[_to].add(_value);
    balances[_from] = balances[_from].sub(_value);
    allowed[_from][msg.sender] = _allowance.sub(_value);
    Transfer(_from, _to, _value);
    return true;
  }

  /**
   * @dev Aprove the passed address to spend the specified amount of tokens on beahlf of msg.sender.
   * @param _spender The address which will spend the funds.
   * @param _value The amount of tokens to be spent.
   */
  function approve(address _spender, uint256 _value) returns (bool) {

    // To change the approve amount you first have to reduce the addresses`
    //  allowance to zero by calling `approve(_spender, 0)` if it is not
    //  already 0 to mitigate the race condition described here:
    //  https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
    require((_value == 0) || (allowed[msg.sender][_spender] == 0));

    allowed[msg.sender][_spender] = _value;
    Approval(msg.sender, _spender, _value);
    return true;
  }

  /**
   * @dev Function to check the amount of tokens than an owner allowed to a spender.
   * @param _owner address The address which owns the funds.
   * @param _spender address The address which will spend the funds.
   * @return A uint specifing the amount of tokens still avaible for the spender.
   */
  function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
    return allowed[_owner][_spender];
  }
}

/**
 * @title Mintable token
 * @dev Simple ERC20 Token example, with mintable token creation
 * @dev Issue: * https://github.com/OpenZeppelin/zeppelin-solidity/issues/120
 * Based on code by TokenMarketNet: https://github.com/TokenMarketNet/ico/blob/master/contracts/MintableToken.sol
 */

contract MintableToken is StandardToken, Ownable {
  event Mint(address indexed to, uint256 value);
  event MintFinished();

  bool public mintingFinished = false;

  modifier canMint() {
    require(!mintingFinished);
    _;
  }

  /**
   * @dev Function to mint tokens
   * @param _to The address that will recieve the minted tokens.
   * @param _amount The amount of tokens to mint.
   * @return A boolean that indicates if the operation was successful.
   */
  function mint(address _to, uint256 _amount) onlyOwner canMint returns (bool) {
    totalSupply = totalSupply.add(_amount);
    balances[_to] = balances[_to].add(_amount);
    Mint(_to, _amount);
    return true;
  }

  /**
   * @dev Function to stop minting new tokens.
   * @return True if the operation was successful.
   */
  function finishMinting() onlyOwner returns (bool) {
    mintingFinished = true;
    MintFinished();
    return true;
  }
}

/**
 * @title Test Token Contract
 * @dev The main Test Token Contract
 * 
 * ABI 
 * [{"constant":true,"inputs":[],"name":"mintingFinished","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"name","outputs":[{"name":"","type":"string"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_spender","type":"address"},{"name":"_value","type":"uint256"}],"name":"approve","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"totalSupply","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_from","type":"address"},{"name":"_to","type":"address"},{"name":"_value","type":"uint256"}],"name":"transferFrom","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"decimals","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_to","type":"address"},{"name":"_amount","type":"uint256"}],"name":"mint","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"tradingStarted","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_startStop","type":"bool"}],"name":"startTrading","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_owner","type":"address"}],"name":"balanceOf","outputs":[{"name":"balance","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"finishMinting","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"owner","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"symbol","outputs":[{"name":"","type":"string"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_to","type":"address"},{"name":"_value","type":"uint256"}],"name":"transfer","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_owner","type":"address"},{"name":"_spender","type":"address"}],"name":"allowance","outputs":[{"name":"remaining","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"payable":false,"type":"function"},{"anonymous":false,"inputs":[{"indexed":true,"name":"to","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Mint","type":"event"},{"anonymous":false,"inputs":[],"name":"MintFinished","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"owner","type":"address"},{"indexed":true,"name":"spender","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Approval","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"from","type":"address"},{"indexed":false,"name":"to","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Transfer","type":"event"}]
 */
contract TestToken is MintableToken {

  string public name = "Test Token";
  // change this before creating for production
  string public symbol = "TEST";
  uint public decimals = 18;

  bool public tradingStarted = false;

  /**
   * @dev modifier that throws if trading has not started yet
   */
  modifier hasStartedTrading() {
    require(tradingStarted);
    _;
  }

  /**
   * @dev Allows the owner to start/stop the trading.
   */
  function startTrading(bool _startStop) onlyOwner {
    // change this before creating for production
    tradingStarted = _startStop;
  }

  /**
   * @dev Allows anyone to transfer the tokens once trading has started
   * @param _to the recipient address of the tokens. 
   * @param _value number of tokens to be transfered. 
   */
  function transfer(address _to, uint256 _value) hasStartedTrading returns (bool) {
    super.transfer(_to, _value);
    return true;
  }

   /**
   * @dev Allows anyone to transfer the tokens once trading has started
   * @param _from address The address which you want to send tokens from
   * @param _to address The address which you want to transfer to
   * @param _value uint the amout of tokens to be transfered
   */
  function transferFrom(address _from, address _to, uint256 _value) hasStartedTrading returns (bool) {
    super.transferFrom(_from, _to, _value);
    return true;
  }
}

/**
 * @title a Test Token Sale Contract
 * @dev The main Test Token Sale Contract
 * 
 * ABI
 * [{"constant":true,"inputs":[],"name":"ended","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"rate","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"Vault","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"authIndex","type":"uint256"}],"name":"getAuthorizer","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"weiRaised","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"recipient","type":"address"},{"name":"tokens","type":"uint256"}],"name":"authorizedCreateTokens","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_auto","type":"bool"}],"name":"setAutoSend","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_startStop","type":"bool"}],"name":"startTrading","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"","type":"address"}],"name":"keys","outputs":[{"name":"","type":"string"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_Vault","type":"address"}],"name":"setVault","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_rate","type":"uint256"}],"name":"changeRate","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"minPay","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"owner","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"autoSend","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"holder","type":"address"}],"name":"getBalanceOf","outputs":[{"name":"balance","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"selfDestruct","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_minPay","type":"uint256"}],"name":"changeMinPay","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"start","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"getTotalSupply","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"etherRaised","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"recipient","type":"address"}],"name":"createTokens","outputs":[],"payable":true,"type":"function"},{"constant":false,"inputs":[{"name":"_addr","type":"address"}],"name":"addAuthorized","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_to","type":"address"},{"name":"_value","type":"uint256"}],"name":"transferMain","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"collect","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"closeSale","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_ended","type":"bool"}],"name":"setEnd","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"key","type":"string"}],"name":"register","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_start","type":"uint256"}],"name":"setStart","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"token","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_addr","type":"address"}],"name":"isAuthorized","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"payable":true,"type":"fallback"},{"anonymous":false,"inputs":[{"indexed":false,"name":"recipient","type":"address"},{"indexed":false,"name":"wei_amount","type":"uint256"},{"indexed":false,"name":"token_amount","type":"uint256"},{"indexed":false,"name":"rate","type":"uint256"}],"name":"LogBuy","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"recipient","type":"address"},{"indexed":false,"name":"pay_amount","type":"uint256"}],"name":"LogAuthCreate","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"issuedSupply","type":"uint256"},{"indexed":false,"name":"restrictedTokens","type":"uint256"}],"name":"LogSaleClosed","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"user","type":"address"},{"indexed":false,"name":"key","type":"string"}],"name":"LogRegister","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"amount","type":"uint256"}],"name":"LogCollect","type":"event"}]
 */
contract TestTokenSale is Ownable, Authorizable {
  using SafeMath for uint256;
  event LogBuy(address recipient, uint256 wei_amount, uint256 token_amount, uint256 rate);
  event LogAuthCreate(address recipient, uint256 pay_amount);
  event LogSaleClosed(uint256 issuedSupply, uint256 restrictedTokens);
  event LogRegister(address user, string key);
  event LogCollect(uint256 amount);

  TestToken public token = new TestToken();

  // change this before creating for production
  address public Vault = 0xca35b7d915458ef540ade6068dfe2f44e8fa733c; // remix wallet

  // how many token units a buyer gets per ether
  uint256 public rate = 10000000000000000000000; // 10k tokens per ether

  // change this before creating for production
  uint public start = 1; //1509282000; //new Date("Oct 29 2017 13:00:00 UTC").getTime() / 1000
  bool public ended = false;
  // amount of raised money in wei
  uint256 public weiRaised;
  uint256 public minPay = 10000000000000000; // 0.01 ether

  bool public autoSend = false;
  mapping (address => string) public keys;

  /**
   * @dev Allows anyone to create tokens by depositing ether.
   * @param recipient = address to receive tokens. 
   */
  function createTokens(address recipient) public payable {
    require(recipient != 0x0);
    require(validPurchase());
    uint256 tokens = rate.mul(msg.value).div(1 ether);
    require(token.mint(recipient, tokens));
    weiRaised = weiRaised.add(msg.value);
    // If transfer does not use a lot of gas, then autoSend should not be used
    if (autoSend) {
        Vault.transfer(msg.value);
    }
    LogBuy(recipient, msg.value, tokens, rate);
  }
  // @return true if the transaction can buy tokens
  function validPurchase() internal constant returns (bool) {
    bool minPurchase = msg.value >= minPay;
    return (now > start) && !ended && minPurchase;
  }
  /**
   * @dev Let owner collect ETH
   */
  function collect() onlyOwner returns (uint256) {
    uint256 amount = this.balance;
    Vault.transfer(this.balance);
    LogCollect(amount);
    return amount;
  }
  /**
   * @dev Let owner turn on/off
   */
  function setAutoSend(bool _auto) public onlyOwner {
    autoSend = _auto;
  }
  /**
   * @dev Allows the owner to set the starting time.
   * @param _start the new _start
   */
  function setStart(uint256 _start) public onlyOwner {
    start = _start;
  }
  /**
   * @dev Allows the owner to set the Vault address
   * @param _Vault the Vault address
   */
  function setVault(address _Vault) public onlyOwner {
    require(_Vault != 0x0);
    if (_Vault != address(0)) {
      Vault = _Vault;
    }
  }
  /**
   * @dev Allows the owner to set the rate.
   * @param _rate the exchangerate
   */
  function changeRate(uint256 _rate) public onlyOwner {
    require(_rate > 0);
    rate = _rate;
  }
  /**
   * @dev Allows the owner to close sale. This will create the 
   * restricted tokens.
   * Then the ownership of the token contract is transfered 
   * to this owner.
   */
  function closeSale() public onlyOwner returns (bool) {
    uint256 issuedTokenSupply = token.totalSupply();
    uint256 restrictedTokens = issuedTokenSupply.mul(42857).div(100000);
    require(token.mint(Vault, restrictedTokens));
    ended = true;
    token.transferOwnership(owner); // Don't know why TenX has this. Doesn't it tranfer ownership to same owner?
    LogSaleClosed(issuedTokenSupply, restrictedTokens);
    return true;
  }
  /**
   * @dev Fallback function which receives ether and created the appropriate number of tokens for the 
   * msg.sender.
   */
  function() external payable {
    createTokens(msg.sender);
  }
  /**
   * @dev Allows the owner to end the sale.
   * @param _ended - true or false
   */
  function setEnd(bool _ended) public onlyOwner returns (bool) {
    ended = _ended;
    return ended;
  }
  /**
   * @dev Show amount raised in ETH
   */
  function etherRaised() public constant returns (uint256) {
      return weiRaised.div(1000000000000000000);
  }
  /**
   * @dev Allows the owner to change minimum payment.
   * @param _minPay = minimum payment
   */
  function changeMinPay(uint256 _minPay) onlyOwner returns (bool) {
      minPay = _minPay;
      return true;
  }
  /**
   * @dev Allows any holder to get balance of his/her tokens
   * @param holder = address of holder
   */
  function getBalanceOf(address holder) returns (uint256 balance) {
      return token.balanceOf(holder);
  }
  /**
   * @dev Allows anyone to get total number of tokens created
   */
  function getTotalSupply() returns (uint256) {
      return token.totalSupply();
  }

  /*  This cannot work because msg.sender in BasicToken is zero or blank */
  function transfer(address _to, uint256 _value) returns (bool) {
    token.transfer(_to, _value);
    return true;
  }
  /**
   * @dev Allows the owner start or stop trading
   * @param _startStop = true or false
   */
  function startTrading(bool _startStop) onlyOwner {
    token.startTrading(_startStop);
  }
  /**
   * @dev Allows the owner to destroy contract
   */
  function selfDestruct() onlyOwner returns (bool) {
      selfdestruct(Vault);
      return true;
  }
  /**
   * @dev For user to register their new public key to map holder's tokens to new blockchain tokens
   * Read full key import policy.  Manually registering requires a base58
   * encoded using the STEEM, BTS, or EOS public key format, for now.  Subject to change.
   * @param key = holder's public key 
   */
  function register(string key) {
    assert(bytes(key).length <= 64);
    keys[msg.sender] = key;
    LogRegister(msg.sender, key);
  }
  /**
   * @dev Allows authorized access to create tokens. This is used to pay helpers.
   * @param recipient = address to receive tokens.
   * @param tokens = number of tokens to be created. 
   */
  function authorizedCreateTokens(address recipient, uint tokens) public onlyAuthorized {
    token.mint(recipient, tokens);
    LogAuthCreate(recipient, tokens);
  }
}
2
  • Transfer Ownership

    I understand that the token in TenX is separate contract from the crowdsale. To allow the crowdsale contract to create new tokens you set it as the owner of the token contract. The owner of the token can create new tokens through mint function.

    At the end of the crowdsale minting of new tokens is disabled and ownership is transfered to the owner of the crowdsale (I suppose a team account) so they can act in the case of an emergency.

  • Transfer not working

    Generally you do not want to allow transfers during the crowdsale. The transfer function should not exist in the crowdsale contract, it should only exist in the token contract.

  • Thanks for your answers. However, based on token.transferOwnership(owner) , the ownership is transferred to the variable "owner", which is still the crowdsale contract, not a team account. So, I don't understand the purpose of this line. Is it a bug or oversight on the part of TenX? – Curt Aug 25 '17 at 15:30
  • The call token.transferOwnership(owner) is executed inside the crowdsale contract so owner points to the owner of the crowdsale contract (which I assume is a team account). – Ismael Aug 25 '17 at 16:38
  • See "My code", which is largely copied from TenX. TokenSale is TestToken, and TestToken is MintableToken and MintableToken is Ownable. In contract Ownable, variable "owner" is set to msg.sender. Therefore, owner is set to TokenSale's (crowdsale contract) address. When token.transferOwnership(owner) is run in finishMinting, there is no change to the value of owner. – Curt Aug 25 '17 at 16:54
  • The in your case you do not need to call transferOwnership. – Ismael Aug 25 '17 at 18:04

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