How to Create One-Time Payments Using Express Checkout.curl

DoExpressCheckoutPayment.curl

curl -s --insecure https://api-3t.sandbox.paypal.com/nvp -d 
"USER=<callerID>
&PWD=<callerPswd>
&SIGNATURE=<callerSig>
&METHOD=DoExpressCheckoutPayment
&VERSION=93
&TOKEN=<tokenValue>
&PAYERID=<payerID>                      # customer's unique PayPal ID
&PAYMENTREQUEST_0_PAYMENTACTION=SALE    # payment type
&PAYMENTREQUEST_0_AMT=19.95             # transaction amount
&PAYMENTREQUEST_0_CURRENCYCODE=USD"     # transaction currency, e.g. US dollars

GetExpressCheckoutDetails.curl

curl -s --insecure https://api-3t.sandbox.paypal.com/nvp -d 
"USER=<callerID>
&PWD=<callerPswd>
&SIGNATURE=<callerSig>
&METHOD=GetExpressCheckoutDetails
&VERSION=93
&TOKEN=<tokenValue>"

SetExpressCheckout.curl

curl -s --insecure https://api-3t.sandbox.paypal.com/nvp -d
"USER=<callerID>                         # User ID of the PayPal caller account
&PWD=<callerPswd>                        # Password of the caller account
&SIGNATURE=<callerSig>                   # Signature of the caller account
&METHOD=SetExpressCheckout
&VERSION=93
&PAYMENTREQUEST_0_PAYMENTACTION=SALE     # type of payment
&PAYMENTREQUEST_0_AMT=19.95              # amount of transaction
&PAYMENTREQUEST_0_CURRENCYCODE=USD       # currency of transaction
&RETURNURL=http://www.example.com/success.html  # URL of your payment confirmation page
&CANCELURL=http://www.example.com/cancel.html"  # URL redirect if customer cancels payment