how can i make a payment gateway in php? by a payment gateway(for those who dont know) what i mean is,

a script where an end user would enter his credit card number and code and after having his credit card verified the script charges his card for the amount of the products price then the product will be sent to the user or a service will be provided for the user etc..

also if you know any 3rd party companies please let me know. the reason i dont want to go with paypal is because i want something on the spot where the person is charged and provided the service the same time of the purchase. such as when you go to amazon.com you purchase something and you are automatically charged for the product you purchase.

thanks

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