Bitcoin Forum

I'm new to bitcoin and I still can't find a clear answer to my doubt.

If I buy bitcoins on an exchange which won't disclose my private keys, it means I can't send the coins to an address of, say, my electrum cold wallet?
Is this the case? I would be forced to sell and buy only within the exchange? 
If so, how can I use my coins for something else than trading or investing?  ???

The next question is, is there a list of exchanges that disclose your own private keys?

Yes, you can. But not directly like you would with a wallet you control. All exchanges will let you ask for a withdraw of your coins, which will be sent to the address you choose previously.

You will see a withdraw page with instructions on how to request your coins.

No.

There is some good reading at localbitcoins dot com.  Transfer of coins from your wallet there to an Electrum wallet is fast and safe.

It's cos the coins, in a lot of cases, aren't really in your wallet when in an exchange, only when depositing to, and withdrawing from the site, are the actual wallets used, this to avoid fees. I think the site would be reluctant to give out keys for wallet associated with you as they would lose fees from it.

Most exchanges will not give you access to the private keys for simplicity reasons but as soon as you move them to a wallet such as bitcoin core, you will have access to them.